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Application Guide - NP900 Series

 

 

 363 (504

)

 

A996A 

Table 3.5.3.2-224 Environmental settings 

Name 

Range 

Step 

Default 

Description 

Object max temp (tmax = 

100%) 

0…500 deg 

1 deg 

90 

Maximum allowed temperature for 

the protected object. Default setting 

is +90 degrees and it suits for Celsius 

range and for PEX insulated cables 

Ambient temp sel 

0: Manual set 

1: RTD 

0:Manual 

set 

Selection whether fixed or measured 

ambient temperature should be used 

for the thermal image biasing. 

Man.Amb.Temp.Set 

0…500 deg 

1 deg 

15 deg 

Manual fixed ambient temperature 

setting for the thermal image biasing. 

For underground cables commonly is 

used 15 degrees Celsius. Setting is 

visible if Ambient temp sel is set to 

“Manual set”. 

RTD Amb.Temp.Read 

0…500 deg 

1 deg 

15 deg 

RTD ambient temperature reading for 

the thermal image biasing. Setting is 

visible if Ambient temp sel is set to 

“RTD”. 

Ambient lin. or curve 

0:Linear est. 

1:Set curve 

0:Linear 

est 

Selection of ambient temperature 

correction either by internally 

calculated compensation based into 

end temperatures or user settable 

curve. Default setting is 0:Linear corr, 

which means internally calculated 

correction for ambient temperature. 

Temp.reference (tref) 

k

amb

=1.0 

-60…500 deg 

1 deg 

15 deg 

Temperature reference setting. In this 

temperature manufacturer 

presumptions apply and the thermal 

correction factor is 1.00 (rated 

temperature). For ground dug cables 

this is usually 15  

̊

C and in air 25  

̊

C. 

Setting is visible if  Ambient lin. or 

curve is set to “Linear est.” 

Max ambient temp 

0…500 deg 

1 deg 

45 deg 

Maximum ambient temperature 

setting. If measured temperature is 

more than maximum set temperature 

the set correction factor for maximum 

temperature shall be used.  Setting is 

visible if  Ambient lin. or curve is set 

to “Linear est.” 

k at max amb temp 

0.01…5.00 xIn 

0.01 xIn  1.00 xIn 

Temperature correction factor for 

maximum ambient temperature 

setting. Setting is visible if  Ambient 

lin. or curve is set to “Linear est.” 

Min ambient temp 

-60…500 deg 

1 deg 

0 deg 

Minimum ambient temperature 

setting. If measured temperature is 

less than minimum set temperature 

the set correction factor for minimum 

temperature shall be used. Setting is 

visible if  Ambient lin. or curve is set 

to “Linear est.” 

k at min amb temp 

0.01…5.00 xIn 

0.01 xIn  1.00 xIn 

Temperature correction factor for 

minimum ambient temperature 

setting. Setting is visible if  Ambient 

lin. or curve is set to “Linear est.” 

Amb.Temp.ref1...10 

-50.0…500.0 

deg 

0.1 deg 

15 deg 

Temperature reference points for the 

user settable ambient temperature 

coefficient curve. Setting is visible if  

Summary of Contents for NP900 Series

Page 1: ......

Page 2: ...o become familiar with it before trying to install operate service or maintain it Electrical equipment should be installed operated serviced and maintained only by qualified personnel Local safety reg...

Page 3: ...alance I2 46 46R 92 3 2 8 Harmonic over current IH 50H 51H 68H 100 3 2 9 Circuit breaker failure protection CBFP 50BF 106 3 2 10 Restricted earth fault cable end differential REF I0D 87N 118 3 2 11 Th...

Page 4: ...3 5 1 Transformer status monitoring functions 307 3 5 2 Differential protection ID 87 313 3 5 3 Thermal overload for transformer 49T 357 3 5 4 Volts per Hertz over excitation 24 367 3 6 Control funct...

Page 5: ...compatibility HMI Human machine interface HW Hardware IED Intelligent electronic device IO Input output LED Light emitting diode LV Low voltage MV Medium voltage NC Normally closed NO Normally open R...

Page 6: ...ever more demanding expectations ICE chose to design produce and distribute a complete range of equipment s supporting the implementation of the intelligence and connections required for a fully opti...

Page 7: ...former transforms according to its ratios This current is measured by the protection IED NOM o Nominal primary current of the load Load in this means can be any electrical apparatus which produces or...

Page 8: ...en Also in the NP900 series feeder protection IEDs the scaling can be set according to protected object nominal current Normally the primary current ratings for phase current transformers are 10A 12 5...

Page 9: ...1A Load nominal 36A Phase currents are connected to residual connection into the I01 residual input Phase current CT secondary currents starpoint is towards the line For the scaling of the currents t...

Page 10: ...urrent is the phase CT nominal Per unit scaling factors to primary and secondary values are also shown In this case the scaling factors are directly the set primary and secondary currents of the set C...

Page 11: ...tio of CT primary to object nominal current If coarse residual current I01 is wanted to be used for CT sum input then it should be set to phase current CT ratings 100 1A Figure 3 1 1 1 5 Residual curr...

Page 12: ...ng selection does not have effect to that Only effect is now that the per unit system in the relay is scaled to either transformer nominal or the protected object nominal and this makes the settings i...

Page 13: ...at the scaling measurement to In is set accordingly either to Object In or CT nominal If working with CT s if possible check the actual ratings from the CT s as well since in some cases the actual CT...

Page 14: ...2 0 67 xIn 0 00 deg I0Calc 0 67 xIn 0 00 deg Resolution Change wires to opposite in CT module connectors 1 2 Or from the Transformers Phase CT scaling select IL1 polarity to Invert Phase L2 B polarity...

Page 15: ...o opposite in CT module connectors 3 5 Phase L3 C and L1 A switch place network rotation wrong Measurements Phase currents Sequence currents IL1 1 00 xIn 0 00 deg IL2 1 00 xIn 120 00 deg IL3 1 00 xIn...

Page 16: ...om p u value to secondary current Table 3 1 1 4 3 Settings of the residual I01 CT scaling in NP900 Name Range Step Default Description I01 CT primary 1 5000 0 A 0 1A 100 0A Rated primary current of th...

Page 17: ...rements in NP900 Name Range Step Description Primary Phase current ILx 0 00 1000000 0A 0 01A Primary measurement from each phase current channel fundamental frequency RMS current Phase current ILx TRM...

Page 18: ...0 00 500 0 xIn 0 01xIn Per unit measurement peak to peak current from I01 residual current measurement channel Peak to peak current I02 0 00 500 0 xIn 0 01xIn Per unit measurement peak to peak curren...

Page 19: ...360 00 deg 0 01deg Calculated residual current angle measurement Table 3 1 1 5 13 Per unit sequence current measurements in NP900 Name Range Step Description Positive sequence current 0 00 1250 0 xIn...

Page 20: ...nent for current input IL3 I01 Harmonics I01 fund I01 31harm 0 00 1000000 0A 0 01A Per unit primary and secondary harmonics per component for current input I01 I02 Harmonics I02 fund I02 31harm 0 00 1...

Page 21: ...imary and secondary voltages In modern IEDs like NP900 series devices the scaling calculation is done internally after the voltage transformer primary and secondary voltages are given Normally the pri...

Page 22: ...V U4 VT secondary 100V Zero sequence voltage is connected similar way with Line to neutral voltages U0 In case of incorrect wiring all polarities can be switched individually by 180 degrees in IED If...

Page 23: ...ndary ratio Per unit scaling factors to primary and secondary values are also shown Triggering of voltage protection stage can be based on single dual or all three fault loops Fault loops are either l...

Page 24: ...to line voltages are measured the third one is calculated based on U12 and U23 vectors When measuring line to line voltages the line to neutral voltages can be calculated if U0 is measured and known V...

Page 25: ...is presented relay behavior when nominal voltage is injected to the relay and the IED is measuring line to neutral voltages Part of the available information from the IED is presented as well Figure 3...

Page 26: ...urement mode may be wrong check from Measurement Transformers VT Module that the settings match for what is expected Measured voltage amplitude does not match for one measured phase or calculated U0 i...

Page 27: ...U3 Res SS VT secondary 0 2 400V 0 1V 100 0V Secondary nominal voltage of connected U0 or SS VT Valid only in 2LL U3 U4 mode U4 Res SS VT primary 1 1000000V 0 1V 20000 0V Primary nominal voltage of co...

Page 28: ...primary secondary voltage ratio of voltage channel U4 U4 scaling factor p u Pri IED voltage channel U4 feedback value scaling factor from p u value to primary voltage U4 scaling factor p u Sec IED vo...

Page 29: ...Volt pri 0 00 1000000 00 xUn 0 01V Primary measurement from calculated negative sequence voltage Zero seq Volt pri 0 00 1000000 00 xUn 0 01V Primary measurement from calculated zero sequence voltage...

Page 30: ...age System volt U3 mag 0 00 1000000 00V 0 01V Primary measured fundamental frequency RMS Synchro check SS voltage Valid only in 2LL U3 U4 mode System volt U4 mag 0 00 1000000 00V 0 01V Primary measure...

Page 31: ...G AND SAMPLING In NP900 series the measurement sampling can be set to frequency tracking mode or fixed user given frequency sampling mode Benefit of the frequency tracking is that the measurements are...

Page 32: ...ndependent measurement As can be noted generally that the frequency dependent sampling improves the measurement accuracy significantly also there can be seen that the measurement hardware is not linea...

Page 33: ...ce 2 Trackable 3 Reference 1 2 Trackable 4 Reference 3 Trackable 5 Reference 1 3 Trackable 6 Reference 2 3 Trackable 7 All References Trackable Frequency tracker quality If the current or voltage meas...

Page 34: ...ng to forward exported or reverse imported direction LINE TO NEUTRAL VOLTAGES AVAILABLE Power is calculated from line to neutral voltages and phase currents In case line to line voltages are connected...

Page 35: ...n can be indicated simply by using Cos Cosine phi is calculated according the following formula 3PH Cos phi P S L1 Cos phi PL1 SL1 L2 Cos phi PL2 SL2 L3 Cos phi PL3 SL3 Direction of reactive power is...

Page 36: ...3 1 4 2 SETTINGS Table 3 1 4 2 31 Power and Energy meas settings in NP900 Name Range Step Default Description EP meas 3ph 0 Disabled 1 Enabled 0 Disabled Enable active energy measurement EQ meas 3ph 0...

Page 37: ...escription DC 1 4 Pulse out OUT1 OUT5 or more amount corresponds with order code None selected Controlled physical outputs selection 3 1 4 3 POWER MEASUREMENTS Following power calculations are availab...

Page 38: ...direction 3 1 4 4 ENERGY MEASUREMENTS Following energy calculations are available when voltage and current cards are available Table 3 1 4 4 38 Three phase energy calculation in NP900 Name Range Step...

Page 39: ...Imp React Ind E bal MVarh 1x106 1x106 MVarh 0 01MVarh Sum of imported and exported phase L1 reactive inductive energy Table 3 1 4 4 40 Phase L2 energy calculation in NP900 Name Range Step Description...

Page 40: ...106 MVarh 0 01MVarh Phase L3 total exported reactive inductive energy L3 Imp React Ind E Mvarh 1x106 1x106 MVarh 0 01MVarh Phase L3 total imported reactive inductive energy L3 Exp Imp React Ind E bal...

Page 41: ...ltages Line to line VA 100 00V 30 00 VB 100 00V 90 00 Currents IL1 2 500V 0 00 IL2 2 500V 120 00 IL3 2 500V 120 00 S U12 IL1 U23 IL2 S 100 2 5 100 2 5 500 VA secondary 20 00 MVA primary P U12 IL1 cos...

Page 42: ...ONS 3 2 1 GENERAL PROPERTIES OF A PROTECTION FUNCTION In following flowchart is described the basic structure of any protection function Basic structure is composed of the analog measurement values co...

Page 43: ...asic structure the difference is described in the corresponding chapter of the manual 3 2 1 1 PICK UP CHARACTERISTICS Pick up of the function is controlled by Xset setting parameter which defines the...

Page 44: ...directly equal to start signal generation of the function Start signal is allowed if blocking condition is not active Figure 3 2 1 1 23 Measurement range in relation to the nominal current The In mag...

Page 45: ...ng mode is activated User settable variables are binary signals from the system Blocking signal needs to reach the IED minimum of 5 ms before the set operating delay has passed for blocking to be acti...

Page 46: ...on of the delay type time counter Selection possibilities are dependent IDMT Inverse Definite Minimum Time and independent DT Definite Time characteristics Definite Min operating time delay 0 000 1800...

Page 47: ...Delay Type is selected to IDMT IEEE and ANSI standard delay characteristics ANSI Normal Inverse Very Inverse Extremely inverse Long time inverse characteristics IEEE Moderately Inverse Very Inverse Ex...

Page 48: ...tting A Operating characteristics constant B Operating characteristics constant C Operating characteristics constant Standard delays IEC constants Type A B Normally Inverse NI 0 14 0 02 Extremely Inve...

Page 49: ...Application Guide NP900 Series 49 504 A996A Figure 3 2 1 3 25 Definite time operating characteristics...

Page 50: ...Application Guide NP900 Series 50 504 A996A Figure 3 2 1 3 26 IEC predefined characteristics NI VI LTI and EI...

Page 51: ...Application Guide NP900 Series 51 504 A996A Figure 3 2 1 3 27 IEEE ANSI predefined characteristics EI LTI NI and VI...

Page 52: ...Application Guide NP900 Series 52 504 A996A Figure 3 2 1 3 28 IEEE predefined characteristics EI MI and VI...

Page 53: ...Application Guide NP900 Series 53 504 A996A Figure 3 2 1 3 29 Parameters A B and C effect to the characteristics...

Page 54: ...their ranges are documented in the function blocks respective chapters RI type characteristic is used to get time grading with mechanical relays Equation 1 RI type characteristic is used to get time...

Page 55: ...ignal is reset after set release time delay Time calc reset after release time No Yes Yes Operating timer resetting characteristics selection When active the operating time counter is reset after set...

Page 56: ...Guide NP900 Series 56 504 A996A Figure 3 2 1 4 31 Delayed pick up release delay counter is reset at signal drop off Figure 3 2 1 4 32 Delayed pick up release delay counter value is held during the re...

Page 57: ...e release time counting 3 2 1 5 STAGE FORCING In NP900 series relays it is possible to test the logic and the operation of the protection system of the relay by controlling the state of the protection...

Page 58: ...ode the operation can be selected for definite time or IDMT For IDMT operation IEC and ANSI standard time delays are supported as well as custom parameters Function includes CT saturation checking whi...

Page 59: ...by the NOC function Signal Description Time base IL1PP Peak to peak measurement of phase L1 A current 5 ms IL2PP Peak to peak measurement of phase L2 B current 5 ms IL3PP Peak to peak measurement of...

Page 60: ...lock signal is checked in the beginning of each program cycle Blocking signal is received from the blocking matrix for the function dedicated input If the blocking signal is not activated when the pic...

Page 61: ...this In the following table are presented the setting parameters for the function time characteristics Table 3 2 2 4 47 Operating time characteristics setting parameters Name Range Step Default Descri...

Page 62: ...teristics B 0 0000 5 0000 0 0001 0 1850 Setting is active and visible when Delay Type is selected to IDMT Constant B for IEC IEEE characteristics C 0 0000 250 0000 0 0001 0 0200 Setting is active and...

Page 63: ...ss data values Table 3 2 2 5 49 Event codes of the NOC function instances 1 4 Event Number Event channel Event block name Event Code Description Event Type 1280 20 NOC1 0 Start ON 1 1281 20 NOC1 1 Sta...

Page 64: ...ration Outputs of the function are Start Trip and Blocked signals Setting parameters are static inputs for the function which are changed only by user input in the setup phase of the function Non dire...

Page 65: ...ted the simplified function block diagram of the NEF function Figure 3 2 3 35 Simplified function block diagram of the NEF function 3 2 3 1 MEASURED INPUT VALUES Function block uses analog current mea...

Page 66: ...ing parameter In all possible input channel variations pre fault condition is presented with 20 ms averaged history value from 20 ms of Start or Trip event 3 2 3 2 PICK UP CHARACTERISTICS Pick up of t...

Page 67: ...is issued Blocking signal can be tested also in the commissioning phase of the stage by software switch signal when relay common and global testing mode is activated User settable variables are binar...

Page 68: ...nd industry IED with both voltage and current protection module may have four available instances of the function IDir IDir IDir IDir Function measures constantly phase current magnitudes which on the...

Page 69: ...operational logic consists of input magnitude and angle processing input magnitude selection saturation check threshold comparator block signal check time delay characteristics and output processing...

Page 70: ...amental frequency RMS values True RMS values from the whole harmonic specter of 32 components or peak to peak values 20ms averaged value of the selected magnitude is used for pre fault data registerin...

Page 71: ...nel variations pre fault condition is presented with 20 ms averaged history value from 20 ms of Start or Trip event 3 2 4 2 REAL TIME INFO DISPLAYED OF THE FUNCTION The relays Info page displays usefu...

Page 72: ...s below 1V secondary the angle memory is used for 0 5 seconds Angle memory forces the angle reference to the value that was measured or calculated before the fault Angle memory captures the measured v...

Page 73: ...al will be generated and the function shall not process the situation further If START function has been activated before blocking signal it will reset and the release time characteristics are process...

Page 74: ...instances separately Table 3 2 4 6 58 Register content Event Number Event channel Event block name Event Code Description Event Type Alarm Type 4800 75 DOC1 0 Start ON 1 0 4801 75 DOC1 1 Start OFF 0 0...

Page 75: ...ich are changed only by user input in the setup phase of the function Directional earth fault function utilizes total of eight separate setting groups which can be selected from one common source The...

Page 76: ...k to peak values 20ms averaged value of the selected magnitude is used for pre fault data registering Fault current angle is based on comparison of neutral voltage U0 Both I0 and U0 must be above sque...

Page 77: ...f Start or Trip event 3 2 5 2 PICK UP CHARACTERISTICS Pick up of the DEF function is controlled by I0set setting parameter which defines the maximum allowed measured current U0set setting parameter wh...

Page 78: ...r to faulty feeder Healthy feeders do not trip since capacitive current is floating to opposite direction and selective tripping can be ensured Amplitude of fault current depends of the capacitance of...

Page 79: ...nt and therefore residual current in fault location is close to zero Size of the inductance is chosen according the prospective earth fault current of the network Desired compensation grade is achieve...

Page 80: ...model In directly grounded network the amplitude of single phase fault current is similar to amplitude of short circuit current Directly or small impedance grounded network schemes are normal in tran...

Page 81: ...up and is counting time towards pick up 3 2 5 4 FUNCTION BLOCKING In the blocking element the block signal is checked in the beginning of each program cycle Blocking signal is received from the block...

Page 82: ...r of the DEF function is recorded start trip or blocked On event process data In the table below is presented the structure of DEF function register content This information is available in 12 last re...

Page 83: ...y point for this type of fault appearance is the compensation of earth fault currents with Petersen coil This phenomenon is coming more frequent as utilities are changing the overhead lines to ground...

Page 84: ...have tripped in the same fault including by luck the correct faulty feeder In this later case also in all of the relays logs can be seen the incorrectly started directional earth fault events and rel...

Page 85: ...85 504 A996A Figure 3 2 6 42 Close to resonance tuned medium size network intermittent earth fault seen by faulty feeder relay Figure 3 2 6 43 Close to resonance tuned network intermittent earth faul...

Page 86: ...th fault seen by faulty feeder relay Figure 3 2 6 45 Undercompensated medium size network intermittent earth fault seen by healthy feeder relay As can be seen from the figures the residual voltage in...

Page 87: ...TTENT ALGORITHM DESCRIPTION Patent pending Further information by request 3 2 6 2 SETTING PRINCIPLES The intermittent earth fault protection shall be coordinated with bus bar residual voltage protecti...

Page 88: ...If an intermittent earth fault protection start is used to block regular non intermittent directional earth fault protection the blocking should be applied for both healthy and faulty feeder relays In...

Page 89: ...ers which define the maximum allowed measured residual current and voltage before action from the function The function constantly calculates the ratio in between of the setting and circular buffer ma...

Page 90: ...e by software switch signal when relay common and global testing mode is activated User settable variables are binary signals from the system Blocking signal needs to reach the IED minimum of 5 ms bef...

Page 91: ...order to trip this set amount of spikes must be exceeded If set operating time is reached but calculated spike amount is below this setting function shall release without trip when the FWD reset time...

Page 92: ...nd machine applications of utilities and industry The number of available instances of the function depends of the IED model Function measures constantly negative and positive sequence current magnitu...

Page 93: ...function registers its operation into 12 last time stamped registers and also generates general time stamped ON OFF events to the common event buffer from each of the three output signal In instant o...

Page 94: ...UP CHARACTERISTICS Pick up of the CUB function is controlled by I2set or I2 I1set setting parameters which define the maximum allowed measured negative sequence current or negative positive sequence...

Page 95: ...ignals from the system Blocking signal needs to reach the IED minimum of 5 ms before the set operating delay has passed for blocking to be active in time 3 2 7 4 OPERATING TIME CHARACTERISTICS FOR TRI...

Page 96: ...below t K1 I2meas IN 2 K2 2 t Operating time I2meas Calculated negative sequence IN Nominal current K1 Constant K1 value user settable delay multiplier K2 Pick up setting of the function In the follow...

Page 97: ...Param selection allows the tuning of the constants A and B which allows setting of characteristics following the same formula as the IEC curves mentioned here Delay characteristics IEEE LTI LTVI LTEI...

Page 98: ...et Continue time calculation during release time No Yes No Time calculation characteristics selection If activated the operating time counter is continuing until set release time even the pick up elem...

Page 99: ...0 ms averages Start 200 ms averages I1 I2 IZ mag and ang 0 ms 1800 s 1 8 Depends on the selected mode Event Number Event channel Event block name Event Code Description Event Type 2048 32 CUB1 0 Start...

Page 100: ...p signal can be used In time delayed mode the operation can be selected for definite time or IDMT and the function Start signal can be used for blocking other stages while in cases when the situation...

Page 101: ...residual currents For each measurement input the HOC function block utilizes the fundamental frequency and harmonic components of the selected current input and by user selection the monitored magnitu...

Page 102: ...rmonic 5th harmonic 7th harmonic 9th harmonic 11th harmonic 13th harmonic 15th harmonic 17th harmonic 19th harmonic current 5 ms I01FFT Magnitudes rms of residual I01 current components Fundamental 2n...

Page 103: ...er unit x In or in relation to the fundamental frequency magnitude Measurement input IL1 IL2 IL3 I01 I02 IL1 IL2 IL3 Selection of the measurement input either phase currents or residual currents input...

Page 104: ...further If START function has been activated before blocking signal it will reset and the release time characteristics are processed as in case of when pick up signal is reset From blocking of the fu...

Page 105: ...cr L1 G L1 L2 L3 Start average current Trip 20 ms averages Start 200 ms averages 0 ms 1800 s 1 8 Depends of the selected measurement mode When the measurement input is selected either I01 or I02 the r...

Page 106: ...operating characteristics of the function during normal operation Outputs of the function are CBFP START RETRIP CBFP ACT and BLOCKED signals Setting parameters are static inputs for the function which...

Page 107: ...nal Description Time base IL1RMS Fundamental RMS measurement of phase L1 A current 5 ms IL2RMS Fundamental RMS measurement of phase L2 B current 5 ms IL3RMS Fundamental RMS measurement of phase L3 C c...

Page 108: ...tion constantly calculates the ratio in between of the setting values and measured magnitude Im per all three phases and selected residual current input Reset ratio of 97 is inbuilt in the function an...

Page 109: ...cking signal needs to reach the IED minimum of 5 ms before the set operating delay has passed for blocking to be active in time 3 2 9 4 OPERATING TIME CHARACTERISTICS FOR ACTIVATION AND RESET The oper...

Page 110: ...vailable retrip functionality can be used The trip signal is wired normally to the trip coil of the breaker from the trip output of the IED Retrip is wired in parallel from its own output contact in t...

Page 111: ...current is not decreased under the setting limit first is issued retrip and if the current is not decreased in time also CBFP will be issued to upstream breaker If the primary protection function clea...

Page 112: ...ality Figure 3 2 9 4 52 Retrip and CBFP when selected criteria is current or DO In case when the current based protection activates so that either Iset and or I0Sset current threshold setting is excee...

Page 113: ...o the CBFP functionality Figure 3 2 9 4 53 Into the IED is configured Trip and CBFP Probably the most common application is the case where the circuit breaker trip coil is controlled with the IED trip...

Page 114: ...late the set operating time The tripping of the primary protection stage is not monitored in this configuration and if the current is not decreased under the setting limit CBFP will be issued to upstr...

Page 115: ...ion trips can be excluded from the CBFP functionality Figure 3 2 9 4 56 CBFP when selected criteria is current or DO The counter for CBFP starts to calculate the set operating time either from current...

Page 116: ...wired to the IED digital input and the IED s own trip signal is used for CBFP purpose only In this application the retrip and also CBFP to upstream are also available for different types of requireme...

Page 117: ...r In this application all of the outgoing feeders IED s tripping signals can be connected to one dedicated CBFP IED which operates either on current based or all possible faults CBFP protection 3 2 9...

Page 118: ...measurement for transformers and also this function can be used for Cable End Differential CED functionality Operating principle is low impedance differential protection with settable bias characteri...

Page 119: ...parator block signal check and output processing Inputs for the function are setting parameters and measured and pre processed current magnitudes Function output signals can be used for direct IO cont...

Page 120: ...e of residual input I01 5 ms I02 Ang Fundamental angle of residual input I02 5 ms Selection of the used residual current input AI channel is made with a setting parameter Table 3 2 10 1 86 General set...

Page 121: ...g Residual current mode is more sensitive while max current more coarse Default setting is Residual current I0d pick up 0 01 50 00 of In 0 01 10 Setting for basic sensitivity of the differential chara...

Page 122: ...gram cycle Blocking signal is received from the blocking matrix for the function dedicated input If the blocking signal is not activated when the pick up element activates a Trip signal is generated a...

Page 123: ...g the residual current from phase currents the natural unbalance may be in total around 10 and still the used CT s are in the promised 5P class probably most common CT accuracy class When the current...

Page 124: ...earth faults For this purpose restricted earth fault function is stabile since it monitors only the side it is wired to and compares the calculated and measured residual currents In case of outside e...

Page 125: ...ded activated blocked etc On event process data In the table below is presented the structure of REF function register content This information is available in 12 last recorded events for all provided...

Page 126: ...overcurrent function operating principle for the overload protection applications Thermal image for the TOLF function is calculated according to equation described below t t 1 IMAX IN kSF kAMB 2 e t...

Page 127: ...ctrical device has a homogenous body which is generating and dissipating heat with a rate which is proportional to temperature rise caused by current squared This usually is the case with cables and o...

Page 128: ...or the protected object kmax Ambient temperature correction factor for the maximum temperature tmin Minimum temperature can be set in C or F for the protected object kmin Ambient temperature correctio...

Page 129: ...curve uses linear interpolation for ambient temperature correction with maximum 10 pairs of temperature correction factor pairs Figure 3 2 11 67 Example of the ground temperature and correction coeffi...

Page 130: ...s and the result will be straight line Figure 3 2 11 69 Set correction curve for ambient temperature For the cables this ambient temperature correction is just one correction parameter For the non cha...

Page 131: ...n temperature in given standard conditions Cable current and where it is installed are the most important parameters for setting the thermal image to work properly In addition to this current carrying...

Page 132: ...71 General presumptions of the high voltage cables If the installation conditions vary from the presumption conditions manufacturers may give additional information of how the current carrying capacit...

Page 133: ...orrection coefficients for the current carrying capacity given by the manufacturer As an example of the kSF service factor current carrying capacity factor importance let s calculate cable installatio...

Page 134: ...d from given short circuit withstandability current which is usually 1s value TOLF function uses this same method for estimating the heating time constant Cable 1s 60s I1s IN 2 1s 60s 71400A 680A 2 18...

Page 135: ...to the image 500 mm2 cross sectional 66 kV copper cable is installed with no adjacent cables k 1 into dry gravel and clay k 0 85 ground in depth of 1 5 meter k 0 95 Cable 1s permissible short circuit...

Page 136: ...r would not been set the thermal image would show about 68 C temperature when it in reality would be 96 C Figure 3 2 11 75 Thermal image response with nominal currents and fine tuned kSF correction fa...

Page 137: ...gic consists of input magnitude processing thermal replica comparator block signal check and output processing Inputs for the function are setting parameters and measured and pre processed current mag...

Page 138: ...tal TRMS measurement of phase L1 A current 5 ms IL2RMS Fundamental TRMS measurement of phase L2 B current 5 ms IL3RMS Fundamental TRMS measurement of phase L3 C current 5 ms RTD Temperature measuremen...

Page 139: ...cond value Setting is visible if Set or estimate tau setting is selected to Estimate Max OC time norm 1s 0 1 5 s 0 1 s 1 0 s Time of the maximum rated short circuit current usually 1 second of the pro...

Page 140: ...tref kamb 1 0 60 500 deg 1 deg 15 deg Temperature reference setting In this temperature manufacturer presumptions apply and the thermal correction factor is 1 00 rated temperature For ground dug cabl...

Page 141: ...bit and Trip signals Table 3 2 11 3 94 Pick up characteristics setting SG selectable Name Range Step Default Description Enable TF Alarm 1 0 Disabled 1 Enabled 0 Disabled Enabling Disabling of the Ala...

Page 142: ...ssioning phase of the stage by software switch signal when relay common and global testing mode is activated User settable variables are binary signals from the system Blocking signal needs to reach t...

Page 143: ...for the object 2 Timing status TF Trip delay remaining Time to reach 100 theta TF Trip time to rel Time to theta to reach under trip limit when cooling TF Alarm 1 time to rel Time to theta to reach u...

Page 144: ...c faults is much faster than merely measuring currents and voltages In busbar protection using just the normal protection IEDs could be too slow to disconnect arcs under safe time For example when set...

Page 145: ...ht In Channel4 Light In Channel1 Pressure In Channel2 Pressure In Channel3 Pressure In Channel4 Pressure In ARC Binary input signal I I0 Arc Ph Curr START I I0 Arc Res Curr START I I0 Arc Ph Curr BLOC...

Page 146: ...s Function provides also cumulative counters for TRIP and BLOCKED events for each Zone 3 2 12 1 EXAMPLE SCHEME SETTING The following example gives a better understanding of setting up the arc protecti...

Page 147: ...same way as with normal light sensor If phase overcurrent or residual overcurrent current is needed in tripping decision those can be enabled in the same way as enabling the light sensors in the zone...

Page 148: ...gnal generation of the function Trip signal is allowed if blocking condition is not active 3 2 12 4 FUNCTION BLOCKING In the blocking element the block signal is checked at the beginning of each progr...

Page 149: ...s passed for blocking to be active in time 3 2 12 5 EVENTS The ARC function generates events and registers from the status changes of start trip and blocked To main event buffer it s possible to selec...

Page 150: ...0 4748 74 ARC1 12 Zone4 Trip On 1 1 4749 74 ARC1 13 Zone4 Trip Off 0 0 4750 74 ARC1 14 Zone4 Block On 1 1 4751 74 ARC1 15 Zone4 BlockOff 0 0 4752 74 ARC1 16 Ph Current Blocked On 1 1 4753 74 ARC1 17...

Page 151: ...the function Overvoltage function utilizes total of eight separate setting groups which can be selected from one common source The function can be operating on instant or time delayed mode In time del...

Page 152: ...urement of voltage UL12 V 5 ms UL23RMS Fundamental RMS measurement of voltage UL23 V 5 ms UL31RMS Fundamental RMS measurement of voltage UL31 V 5 ms UL1RMS Fundamental RMS measurement of voltage UL1 V...

Page 153: ...llowed if blocking condition is not active 3 2 13 3 REAL TIME INFO DISPLAYED OF THE FUNCTION The relays Info page displays useful information in real time of the state of the protection function eithe...

Page 154: ...ables are binary signals from the system Blocking signal needs to reach the IED minimum of 5 ms before the set operating delay has passed for blocking to be active in time 3 2 13 5 OPERATING TIME CHAR...

Page 155: ...s of utilities and industry Each IED with voltage protection module has four available instances of the function U U U U Function measures constantly phase voltage or line to line voltage magnitudes F...

Page 156: ...n can operate on instant or time delayed mode In time delayed mode the operation can be selected for definite time or IDMT The operational logic consists of input magnitude processing input magnitude...

Page 157: ...ms U2RMS Fundamental RMS measurement of voltage U2 V 5 ms U3RMS Fundamental RMS measurement of voltage U3 V 5 ms Selection of the used AI channel is made with a setting parameter In all possible input...

Page 158: ...ing Name Description Range Step Default Uset Pick up setting 20 00 120 00 Un 0 01 Un 60 Un U Block setting Block setting If set to zero blocking is not in use Operation explained in the next chapter 0...

Page 159: ...Block setting is set to zero blocking is not in use 3 2 14 4 REAL TIME INFO DISPLAYED OF THE FUNCTION The relays Info page displays useful information in real time of the state of the protection func...

Page 160: ...lease time characteristics are processed as in case of when pick up signal is reset From blocking of the function a HMI display event as well as time stamped blocking event with information of the sta...

Page 161: ...s separately Table 3 2 14 7 112 Register content Date Time Event code Fault type Pretrig voltage Fault voltage Prefault voltage Trip time remaining Used SG dd mm yyyy hh mm ss mss 5696 5893 Descr A A...

Page 162: ...tection is suitable to detect most islanding situation and switch off the mains breaker in order to let the generator supply only loads under their rated power value Therefore overload won t cause any...

Page 163: ...r from each of the three output signals When tripping the function outputs ALARM and TRIP events simultaneously with equivalent time stamp Time stamp resolution is 1ms Function provides also cumulativ...

Page 164: ...3 2 15 2 PICK UP CHARACTERISTICS When a fault appears in the power system and some areas are disconnected the remaining generators connected to the network normally must supply the area which has been...

Page 165: ...ween of the set and measured magnitude m per all selected voltages VJP stage trip signal lasts for 20 milliseconds and resets automatically after the time has passed The setting value is common for al...

Page 166: ...to zero blocking is not in use 3 2 15 4 FUNCTION BLOCKING In the blocking element the block signal is checked in the beginning of each program cycle Blocking signal is received from the blocking matr...

Page 167: ...6 Register content Date Time Event code Fault type Trip da meas dataset Trip da meas dataset Used SG dd mm yyyy hh mm ss mss 9920 9925 Descr L1 2 L2 3 L3 1 and U4 Trip angle difference Alarm angle dif...

Page 168: ...and setting group selection controls the operating characteristics of the function during normal operation 3 2 16 1 POSITIVE SEQUENCE VOLTAGE CALCULATION Below is presented the formula for symmetric...

Page 169: ...between phases 1 and 3 Figure 3 2 16 1 86 Positive sequence component vector examples UL1 UL3 UL2 UL1 Swapped 120 degrees Swapped 240 degrees UL2 UL3 U1 Vector sum divided by three UL1 UL3 UL2 UL1 Sw...

Page 170: ...Below is presented the formula for symmetric component calculation and therefore to NSV calculation U2 1 3 UL1 a2 UL2 aUL3 a 1 120 a2 1 240 UL1 3 Line to neutral voltages See negative sequence calcul...

Page 171: ...nsists of input magnitude processing input magnitude selection threshold comparator block signal check time delay characteristics and output processing Inputs for the function are the operating mode s...

Page 172: ...ignal Description Time base U1RMS Fundamental RMS measurement of voltage U1 V 5 ms U2RMS Fundamental RMS measurement of voltage U2 V 5 ms U3RMS Fundamental RMS measurement of voltage U3 V 5 ms In fund...

Page 173: ...When Uc exceed decrease above below the Uset value will cause pick up operation of the function Table 3 2 16 4 118 Pick up characteristics setting Name Description Range Step Default Pick up terms Dec...

Page 174: ...in use Figure 3 2 16 5 89 Block setting operation example If Block setting is set to zero blocking is not in use 3 2 16 6 REAL TIME INFO DISPLAYED OF THE FUNCTION The relays Info page displays useful...

Page 175: ...is issued Blocking signal can be tested also in the commissioning phase of the stage by software switch signal when relay common and global testing mode is activated User settable variables are binar...

Page 176: ...SG dd mm yyyy hh mm ss mss 1280 1477 Descr Start average voltage Trip 20 ms averages Start 200 ms averages 0 ms 1800 s 1 8 3 2 17 NEUTRAL VOLTAGE U0 59N Neutral overvoltage function NOV is used for n...

Page 177: ...ltage calculation U0 1 3 UL1 UL2 UL3 UL1 3 Line to neutral voltages See zero sequence calculation examples below Normal situation Earth fault in isolated network Close distance short circuit between p...

Page 178: ...elected from one common source The function can be operating on instant or time delayed mode In time delayed mode the operation can be selected for definite time or IDMT For IDMT operation IEC and ANS...

Page 179: ...ction block uses the analog voltage measurement values Function block utilizes fundamental frequency RMS values 20ms averaged value of the selected magnitude is used for pre fault data registering Tab...

Page 180: ...r which defines the maximum allowed measured voltage before action from the function The function constantly calculates the ratio in between of the Uset and measured magnitude Um per all three voltage...

Page 181: ...bles are binary signals from the system Blocking signal needs to reach the IED minimum of 5 ms before the set operating delay has passed for blocking to be active in time 3 2 17 5 OPERATING TIME CHARA...

Page 182: ...s used for instant and time delayed active over power protection In applications like feeder generator and motor protection it is used to detect overload situations by measuring three phase active pow...

Page 183: ...oups which can be selected from one common source The function can operate on instant or time delayed mode The operational logic consists of input magnitude processing threshold comparator two block s...

Page 184: ...Pick up of the OPW function is controlled by Pset setting parameter which defines the maximum allowed measured three phase active power before action from the function The function constantly calculat...

Page 185: ...ltage values and fault type is issued Blocking signal can be tested also in the commissioning phase of the stage by software switch signal when relay common and global testing mode is activated User s...

Page 186: ...on UPW which is used for instant and time delayed active under power protection Under power function detects loss of load conditions when there is no significant loss of current Below is presented for...

Page 187: ...ction outputs START TRIP and BLOCKED signals which can be used for direct IO controlling and also for user logic programming The function registers its operation into 12 last time stamped registers an...

Page 188: ...ve power before action from the function The function constantly calculates the ratio in between of the Pset and measured magnitude Pm Reset ratio of 97 is inbuilt in the function and is always relate...

Page 189: ...ituation further If START function has been activated before blocking signal it will reset and the release time characteristics are processed as in case of when pick up signal is reset From blocking o...

Page 190: ...refault power Trip time remaining Used SG dd mm yyyy hh mm ss mss 4672 4677 Descr Start average power Trip 20 ms averages Start 200 ms averages 0 ms 1800 s 1 8 3 2 20 REVERSE POWER 32R NP900 series IE...

Page 191: ...groups which can be selected from one common source The function can operate on instant or time delayed mode The operational logic consists of input magnitude processing threshold comparator two block...

Page 192: ...of the RPW function is controlled by Pset rev setting parameter which defines the maximum allowed measured three phase active power before action from the function The function constantly calculates t...

Page 193: ...ltage values and fault type is issued Blocking signal can be tested also in the commissioning phase of the stage by software switch signal when relay common and global testing mode is activated User s...

Page 194: ...w or rise above the allowed level When the consumption is larger than the generated power the frequency may drop When more power is generated than is consumed over frequency can occur In generator app...

Page 195: ...y characteristics and output processing Inputs for the function are the operating mode selections setting parameters and measured and pre processed frequency magnitudes and binary input signals Functi...

Page 196: ...easurements menu Table 3 2 22 1 137 Measurement magnitudes used by the FRQV function depends on factory defined Signals Description Time base VT1 U1 U2 U3 L N voltages of first voltage transformer 5 m...

Page 197: ...Pick up setting 10 00 80 00 0 01 Hz 51 Hz fset fset fset fset Pick up setting 5 00 75 00 0 01 Hz 49 Hz The pick up activation of the function is not directly equal to start signal generation of the f...

Page 198: ...in case of when pick up signal is reset From blocking of the function a HMI display event as well as time stamped blocking event with information of the startup voltage values and fault type is issue...

Page 199: ...99 FRQV1 16 f Start ON 1 0 6353 99 FRQV1 17 f Start OFF 0 0 6354 99 FRQV1 18 f Trip ON 1 0 6355 99 FRQV1 19 f Trip OFF 0 0 6356 99 FRQV1 20 f Start ON 1 1 6357 99 FRQV1 21 f Start OFF 0 0 6358 99 FRQ...

Page 200: ...ncy protections One of the most common causes for the frequency to deviate from nominal value is unbalance between generated power and the load demand If the unbalance is big frequency will change rap...

Page 201: ...tion Frequency protection utilizes total of eight separate setting groups which can be selected from one common source The function can operate on instant or time delayed mode The operational logic co...

Page 202: ...nition Signals Description Time base VT1 U1 U2 U3 L N voltages of first voltage transformer 5 ms VT2 U1 U2 U3 L N voltages of second voltage transformer 5 ms 3 2 22 2 PICK UP CHARACTERISTICS AND TIME...

Page 203: ...ing matrix for the function dedicated input If the blocking signal is not activated when the pick up element activates a START signal is generated and the function proceeds to the time characteristics...

Page 204: ...rt ON 1 0 6605 103 DFT1 13 df dt 4 Start OFF 0 0 6606 103 DFT1 14 df dt 4 Trip ON 1 1 6607 103 DFT1 15 df dt 4 Trip OFF 0 0 6608 103 DFT1 16 df dt 5 Start ON 1 0 6609 103 DFT1 17 df dt 5 Start OFF 0 0...

Page 205: ...es of which each can be set to compare from one to three analog measurements The programmable stages have over under and rate of change available with definite time delay to trip from pick up included...

Page 206: ...or the signal Below is an example of a scaling in which primary neutral voltage has been scaled to percentage value so that it would be easier to handle setting up the comparator The scaling factor wa...

Page 207: ...ither of the measured signals fulfills the comparison condition In the same way it is possible to set up comparison of three values Mode Description 0 Mag1 x Mag2 x Mag3 Signal1 x Signal2 x Signal3 mu...

Page 208: ...he absolute value of the measured signal is less than the set pick up level the comparison condition is fulfilled A blocking limit can also be set This means the comparison is not active when measured...

Page 209: ...unit value 17 IL2 5th h IL2 5th harmonic in per unit value 18 IL2 7th h IL2 7th harmonic in per unit value 19 IL2 9th h IL2 9th harmonic in per unit value 20 IL2 11th h IL2 11th harmonic in per unit...

Page 210: ...ue RMS in per unit value 65 I02 TRMS I02 True RMS in per unit value Calculated Description 66 I0Z Mag Current zero sequence in per unit value 67 I0CALC Mag Calculated I0 in per unit value 68 I1 Mag Po...

Page 211: ...eactive power direction 6 SL1 Apparent power L1 S kVA 7 PL1 Active power L1 P kW 8 QL1 Reactive power L1 Q kVar 9 tanfiL1 Phase active power direction L1 10 cosfiL1 Phase reactive power direction L1 1...

Page 212: ...tive Reactance X secondary ohm 47 ZSeqPri Positive Impedance Z primary ohm 48 ZSeqSec Positive Impedance Z secondary ohm 49 ZSeqAngle Positive Impedance Z angle 50 GL1Pri Conductance G L1 primary mS 5...

Page 213: ...RT TRIP and BLOCKED events 3 2 23 3 PICK UP CHARACTERISTICS Pick up of the PGS function is controlled by Pick up setting Mag setting parameter which defines the maximum minimum allowed measured magnit...

Page 214: ...and the release time characteristics are processed as in case of when pick up signal is reset From blocking of the function a HMI display event as well as time stamped blocking event with information...

Page 215: ...function instance 1 10 In the register of the PGS function is recorded start trip or blocked On event process data In the table below is presented the structure of OV function register content This in...

Page 216: ...Series 216 504 A996A Table 3 2 21 5 147 Register content Date Time Event code Mag Mag Set Trip time remaining Used SG dd mm yyyy hh mm ss mss 8576 8637 Descr Magnitude value Measured magnitude Pick up...

Page 217: ...counts motor starts times motor start succeeded times motor has been stopped running time starting time stopped time cumulatively and from last event separately Outputs of the MST function are output...

Page 218: ...ambient temperature factor load is considered to be normal and Load Normal signal is activated If from this condition current exceeds Motor nominal current setting and does not exceed Maximum overloa...

Page 219: ...ome given factor in order that the protection stage does not activate and prevent the motor from starting especially in cases when the low set overcurrent stage operating time is shorter than the star...

Page 220: ...MST_MOTSTART signal is connected to LOGIC_OUT1 signal with AND gate to NOT high overcurrent detect in the MST function When motor is started I stage is blocked if high overcurrent is detected during...

Page 221: ...ting current 0 1 40 0XIn 0 1xIn 6 0 xIn MST TM 49M Ist 48 Im 50M Motors locked rotor current with nominal voltage This setting is used for the automatic curve selection and calculation Also nominal st...

Page 222: ...2 xIn MST TM 49M I 37 Motors no load current This setting defines the Stopped condition when the current is below this setting value Also below this value undercurrent protection stage is locked No l...

Page 223: ...s calculations use this parameter Safe stall time hot 0 1 600 0s 0 1s 15 0s MST TM 49M Ist 48 Im 50M N 48 Safe stall time when motor is hot This setting value is used for the hot thermal stall curve s...

Page 224: ...nt setting from the Motor running situation Missing phase 0 Not active 1 Active 1 0 Missing phase signal is activated if one of the phases measured current is below No load current setting and two pha...

Page 225: ...hase L2 current xIn Phase L3 current xIn Detected change in thermal capacity Motor loading when triggered Event Number Event channel Event block name Event Code Description Event Type 3968 62 MST1 0 M...

Page 226: ...to thermal replica which represents the protected object thermal loading in relation to the effective current in the object Thermal replica includes the calculated thermal capacity used in the memory...

Page 227: ...ndamental frequency component I2 Measured negative sequence current of the fundamental frequency component kNPS Weighting factor of the NPS current biasing to the equivalent current calculation e Eule...

Page 228: ...ditions considering the prevailing conditions in the thermal replica are compensated with ambient temperature coefficient which is constantly calculated and changing when using RTD sensor for the meas...

Page 229: ...kmin Ambient temperature correction factor for the minimum temperature tref Ambient temperature reference can be set in C or F the temperature in which the given manufacturer presumptions apply and th...

Page 230: ...nes this is not the optimal solution especially when the motor drive is not start and stable loading S1 but the motor is stopped and started frequently In following the main reasons and differences of...

Page 231: ...ng method DOL Soft start YD etc will tell whether there is need for another time constants for locked rotor or overloading situations in order to achieve suitable thermal image for the machine Figure...

Page 232: ...are not the time constants of the cable When considering the time constants the only constant is the heating time constant and cooling time constant which in the case of ground dug cable is the same F...

Page 233: ...lt to malfunction of the motor When considering the thermal behavior difference in between of single and multi time constant objects like the cable and electric motor can be seen another fundamental d...

Page 234: ...of that which of these components limits the maximum start up time for the motor Most motors used are rotor limited meaning that the rotor heats up to dangerously high temperatures before the stator A...

Page 235: ...or which temperature conducts to the motor body through the stator windings and from the body to the surrounding air When surface cooled motor is stopped this is the reason why the motor body temperat...

Page 236: ...r in the terms of the heating and endangered parts of the motor Motor thermal image sometimes needs to have a possibility to be adjusted and fine tuned for the application so that it matches the motor...

Page 237: ...ation Guide NP900 Series 237 504 A996A Figure 3 3 2 1 112 Measured motor temperature in heating cooling test Figure 3 3 2 1 113 Matching of the thermal replicas to the measured thermal capacity of the...

Page 238: ...up in possible overload and start up situations motor thermal curves are useful These are usually available on request from manufacturers and the relay operation can be set according to these If motor...

Page 239: ...d when the motor is hot it will be heavily overprotecting allowing the motor only 30 5 second stalling time while the motor can withstand safely about 67 seconds When using dual time constants and dyn...

Page 240: ...240 504 A996A Figure 3 3 2 1 116 Thermal tripping curves with single time constant preload 0 cold and 90 hot Figure 3 3 2 1 117 Thermal tripping curves with dual dynamic time constants and weighting f...

Page 241: ...Application Guide NP900 Series 241 504 A996A Figure 3 3 2 1 118 Thermal cooling curves single cooling time constant Figure 3 3 2 1 119 Thermal cooling curves dynamic dual time constant...

Page 242: ...504 A996A Figure 3 3 2 1 120 Thermal cooling curves dynamic triple time constant motor is running without load in the first part with dedicated time constant Figure 3 3 2 1 121 NPS biased thermal tri...

Page 243: ...Application Guide NP900 Series 243 504 A996A Figure 3 3 2 1 122 NPS biased thermal trip curves with kNPS values 7 and 10...

Page 244: ...ic consists of input magnitude processing thermal replica comparator block signal check and output processing Inputs for the function are setting parameters and measured and pre processed current magn...

Page 245: ...A current 5 ms IL2RMS Fundamental TRMS measurement of phase L2 B current 5 ms IL3RMS Fundamental TRMS measurement of phase L3 C current 5 ms I1 Positive sequence current 5 ms I2 Negative sequence cur...

Page 246: ...if this current is exceeded Min locked rotor current A 0 1 5000A 0 1A MST TM 49M Ist 48 Im 50M Minimum locked rotor current of the motor This setting defines the current limit when in the dynamic cur...

Page 247: ...00 xIn Hot condition theta limit 0 0 100 0 0 1 70 MST N 48 TM 49M Ist 48 Im 50M Setting of the thermal limit Hot Cold situation of the motor When this setting value is not exceed and locked rotor sit...

Page 248: ...mate on line 0 Set manually Selection whether the relay estimates short heating and cooling time constants and the timing for short and long time constants when motor is stopped These values can be se...

Page 249: ...cked rotor and stalled tripping curve selection This setting value is calculated based on information given for LRC and cold safe stall time This setting value is visible when multiple time constants...

Page 250: ...d into the settings given for maximum overload current and minimum locked rotor current With selection Dynamic the thermal replica switches the timeconstants and with setting Fixed no time constants a...

Page 251: ...ult setting is 0 Linear corr which means internally calculated correction for ambient temperature Temp reference tref kamb 1 0 60 500 deg 1 deg 15 deg Temperature reference setting In this temperature...

Page 252: ...perating characteristic of the TOLM function is completely controlled by the thermal image From the thermal image calculated thermal capacity used value can be set IO controls with Alarm 1 Alarm 2 Inh...

Page 253: ...and fault type is issued Blocking signal can be tested also in the commissioning phase of the stage by software switch signal when relay common and global testing mode is activated User settable varia...

Page 254: ...for the object 2 Timing status TM Trip delay remaining Time to reach 100 theta TM Trip time to rel Time to theta to reach under trip limit when cooling TM Alarm 1 time to rel Time to theta to reach u...

Page 255: ...otor time monitoring or inverse operating time based into allowed I2t calculation When using I2t calculation given start up timing the maximum allowed starting time is automatically scaled according t...

Page 256: ...setup is so that the I2t mode is used in the starting and if the application is such that in normal use during motor running locked rotor situations may happen in some part of the duty cycle also the...

Page 257: ...ed this may affect to the starting time of the motor and the setting should be according to the longest possible starting time If the startup situation should always be the same then this expected sta...

Page 258: ...r the LRC function it may be so that the starting is well in action but the user allowed time is spent due to low network voltage caused lower current and lower torque the function may trip before the...

Page 259: ...lly very long due to high accelerating mass In such application it is impossible to note without speed switch if the startup is actually happening or if the load is jammed and the motor is standing st...

Page 260: ...would endanger the motor If the motor stalls after it is started the LRC function may be set to monitor this situation also In the motor protection module is available Mechanical jam function as well...

Page 261: ...ngs of the LRC function Name Range Step Default Prot funcs Description Motor Start 0 DOL 1 StarDelta 2 Softstart 0 DOL MST Ist 48 Motor starting mode selection Direct On Line Star Delta or soft starte...

Page 262: ...M 49M Ist 48 Im 50M Minimum locked rotor current of the motor This setting defines the current limit when in the automatic curve selection and control only short time constant stall is used if this cu...

Page 263: ...e Step Default Description Starting time 0 000 1800 00 0 s 0 005 s 0 040s User settable motor starting time This setting should include the expected normal starting time of the protected motor includi...

Page 264: ...table below is presented the structure of LRC function register content This information is available in 12 last recorded events Table 3 3 3 2 167 Register content Date Time Event code Start Stall ti...

Page 265: ...urers If the given amount of starts is used or time since previous start or start attempt is too short further starting attempts should be blocked by using FSP function allowing the motor to cool down...

Page 266: ...me scale In the example above the motor is allowed four starts in given time t motor is started 4 times and the counter is updated accordingly When only one start is left in the start counter the FSP...

Page 267: ...tuation motor is started 3 times when it is cold and the hot limit is reached before the motor is started 4th time Now the motor was allowed for 4 cold and 3 hot starts and due to the 3 cold starts th...

Page 268: ...protection TM is activated and in use Safe stall time cold 0 1 600 0s 0 1s 20 0s MST TM 49M Ist 48 Im 50M N 48 Safe stall time when motor is cold If this value is not informed then set to same than h...

Page 269: ...ed from operating 3 3 4 2 EVENTS MST function generates events from detected motor status From changes of the events also data register is available Table 3 3 4 2 170 Event codes of the FSP function I...

Page 270: ...gnals Setting parameters are static inputs for the function which are changed only by user input in the setup phase of the function Non directional undercurrent function utilizes total of eight separa...

Page 271: ...asurement of phase L2 B current 5 ms IL3RMS Fundamental RMS measurement of phase L3 C current 5 ms Selection of the used AI channel is made with a setting parameter In all possible input channel varia...

Page 272: ...k up activation of the function is not directly equal to start signal generation of the function Start signal is allowed if blocking condition is not active 3 3 5 3 OPERATING TIME CHARACTERISTICS FOR...

Page 273: ...ted for each instance operation In the function is available 12 last registers where the triggering event of the function start trip or blocked is recorded with time stamp and process data values Tabl...

Page 274: ...while LCR function may allow several tens of seconds starting Outputs of the function are Start Trip and Blocked signals Setting parameters are static inputs for the function which are changed only b...

Page 275: ...amental RMS measurement of phase L3 C current 5 ms Selection of the used AI channel is made with a setting parameter In all possible input channel variations pre fault condition is presented with 20 m...

Page 276: ...tant stall is used if this current is exceeded Min locked rotor current A 0 1 5000A 0 1A MST TM 49M Ist 48 Im 50M Minimum locked rotor current of the motor This setting defines the current limit when...

Page 277: ...TM 49M Ist 48 Im 50M N 48 Safe stall time when motor is hot This setting value is used for the hot thermal stall curve selection in automatic control Also motor start up and number of starts calculati...

Page 278: ...es Operating timer resetting characteristics selection When active the operating time counter is reset after set release time if pick up element is not activated during this time When disabled the ope...

Page 279: ...cking to be active in time 3 3 6 4 EVENTS AND REGISTERS The MJP function generates events and registers from the status changes of start trip and blocked To main event buffer is possible to select sta...

Page 280: ...D external Modbus based RTD modules are supported up to three separate modules which each can hold eight measurement elements For the alarm function RTD 49T can be set 12 individual element monitors w...

Page 281: ...ols There are three separate modules available for selection Figure 3 3 7 137 Set up of the measurement module Used measurement module is selected first and the poll address Module type needs to be se...

Page 282: ...available For the alarm to be active channel measurement must be valid Channel measurement can be invalid if the communication is not working or sensor is broken 3 3 7 1 SETTINGS Table 3 3 7 1 184 Se...

Page 283: ...of the Alarm 2 for the measurement channel x Sx Alarm2 0 1 0 Selection of the measurement higher or lower than setting value mode Sx Alarm2 101 0 20 00 0 deg 0 1 deg 0 0 deg Alarm 2 setting value Ala...

Page 284: ...rm1 Off 4434 69 RTD1 18 S5 Alarm2 On 4435 69 RTD1 19 S5 Alarm2 Off 4436 69 RTD1 20 S6 Alarm1 On 4437 69 RTD1 21 S6 Alarm1 Off 4438 69 RTD1 22 S6 Alarm2 On 4439 69 RTD1 23 S6 Alarm2 Off 4440 69 RTD1 24...

Page 285: ...drops too low synchronous machine can drop out of step One way to for the relay to sense under excitation is by measuring reactive power When the generator induces capacitive power the value of reacti...

Page 286: ...s which can be selected from one common source The operational logic consists of input magnitude processing threshold comparator two block signal check time delay characteristics and output processing...

Page 287: ...agnitudes used by the UEX function Signal Description Time base 3PH Reactive power P Total 3 phase reactive power 5 ms 3 4 2 2 PICK UP CHARACTERISTICS Pick up of the UEX function is controlled by Qset...

Page 288: ...nction Start signal is allowed if blocking condition is not active 3 4 2 3 FUNCTION BLOCKING In the blocking element the block signal is checked at the beginning of each program cycle Blocking signal...

Page 289: ...lable in the function where the triggering event of the function start trip or blocked is recorded with time stamp and process data values Table 3 4 2 5 188 Event codes of the UEX function In the regi...

Page 290: ...on the monitored magnitude can be P E impedance loops or positive sequence impedance For the pre fault data registering 20 ms averaged value of the selected magnitude is used Table 3 4 3 1 190 Measure...

Page 291: ...ocking signal is active when pick up element activates a BLOCKED signal will be generated and the function shall not process the situation further If START function has been activated before blocking...

Page 292: ...s which in VOC functions case decreases the overcurrent pick up level according to set parameters VOC function can work in two ways as a voltage controlled overcurrent protection or voltage restrained...

Page 293: ...the time delay depends on the ratio between the measured current and the current pick up level at the moment This means operation time can also shorten as a result of reduced voltage Figure 3 4 4 144...

Page 294: ...rent 5 ms U1 Positive sequence voltage 5 ms 3 4 4 2 PICK UP CHARACTERISTICS Pick up level of the VOC function is controlled by setting parameters Iv1 Iv2 Ux1 Ux2 and positive sequence voltage measurem...

Page 295: ...is issued Blocking signal can be tested also in the commissioning phase of the stage by software switch signal when relay common and global testing mode is activated User settable variables are binar...

Page 296: ...excessive voltage and eddy current heating Also stray flux will be induced into non laminated components which are not designed to carry flux caused currents For generator overexcitation typically occ...

Page 297: ...ating mode the function outputs START and TRIP events simultaneously with equivalent time stamp Time stamp resolution is 1ms Function provides also cumulative counters for START TRIP and BLOCKED event...

Page 298: ...visible when Delay type either 1 or 2 Inverse operating characteristics time dial setting 0 01 65 00 0 01 0 01 IDMT Multiplier visible when Delay type either 1 or 2 Inverse operating characteristics...

Page 299: ...Application Guide NP900 Series 299 504 A996A Figure 3 4 5 2 145 Inverse and inverse with definite time characteristics with the TimeDial k setting effect...

Page 300: ...s Yes Resetting characteristics selection either time delayed or instant after pick up element is released If activated the start signal is reset after set release time delay Time calc reset after rel...

Page 301: ...ther If START function has been activated before blocking signal it will reset and the release time characteristics are processed as in case of when pick up signal is reset From blocking of the functi...

Page 302: ...eutral voltage for conventional earth fault protection to react Even in the best scenario at least 5 outside of neutral overvoltages range Generators induce some amount of third harmonic neutral volta...

Page 303: ...h can be used for direct IO controlling and also for user logic programming The function registers its operation into 12 last time stamped registers and also generates general time stamped ON OFF even...

Page 304: ...e 3rd Harm Voltage 5 ms 3 4 6 2 PICK UP CHARACTERISTICS Function has an inbuilt low current blocking feature to prevent faulty trips It is set by parameter Low current blocking I1 set If this paramete...

Page 305: ...up element activates a START signal is generated and the function proceeds to the time characteristics calculation If blocking signal is active when pick up element activates a BLOCKED signal will be...

Page 306: ...rded with time stamp and process data values Table 3 4 6 5 204 Event codes of the SEF function In the register of the SEF function is recorded start trip or blocked On event process data In the table...

Page 307: ...cting and monitoring the transformer Basically for standard transformer only name plate data is needed as well as CT scalings to get the relay scale automatically all measurement signals to the transf...

Page 308: ...ted If measured current is in between of low detection and nominal current the Load normal signal is activated If measured current is in between of nominal and heavy overloading current Overloading si...

Page 309: ...0 Manual 1 Yy0 2 Yyn0 3 YNy0 4 YNyn0 5 Yy6 6 Yyn6 7 YNy6 8 YNyn6 9 Yd1 10 YNd1 11 Yd7 12 YNd7 13 Yd11 14 YNd11 15 Yd5 16 YNd5 17 Dy1 18 Dyn1 19 Dy7 20 Dyn7 21 Dy11 22 Dyn11 23 Dy5 24 Dyn5 25 Dd0 26 Dd...

Page 310: ...ion for LV side leads or lags LV side Selection is visible only if vector group is set to 0 Manual set HV LV side phase angle 0 0 360 00 deg 0 1deg 0 0deg TRF DIFF Angle correction factor for HV LV si...

Page 311: ...primary rate Transformer nom impedance 0 01 250 00ohm 0 01ohm 0 00ohm Info Calculated transformer nominal impedance Transformer nom Zk ohm 0 01 250 00ohm 0 01ohm 0 00ohm Info Calculated transformer no...

Page 312: ...ot active 1 Active 1 0 Signal is active when the measured current is in between nominal and high overcurrent limits HVY Overloading 0 Not active 1 Active 1 0 Signal is active when the measured current...

Page 313: ...n for all transformers is that they are crucial and one most important single component in the network which failure in many cases will be seen in wide area While transformers do not have many moving...

Page 314: ...no matter where installed in transmission distribution or generation Monitoring very important as well as fast fault clearing and limiting the transformer internal fault time Differential overcurrent...

Page 315: ...hould be set to delayed tripping characteristics coordinated to the low voltage side relays due to the fact that transformer normal condition energizing and short circuit supply to high low voltage si...

Page 316: ...ansformer special properties like tap changer and auxiliary windings Also transformer vector group is important to know for matching the transformer per unitized vectors as well as HV LV side CT ratio...

Page 317: ...95 which comes from the transformer final test and basically it presents how much the transformer shall be able to feed short circuit current This information is normally available in the transformer...

Page 318: ...uts power of 2 MVA through it the HV side CT secondary current will be 3 85A and LV side CT secondary current will be 4 81A Differential function uses these values for per unitizing the measured curre...

Page 319: ...transformer its HV side is connected to star and low voltage side is connected to delta so that the LV side is in 30 degree lag to HV side vectors The number 1 comes from the angle between the HV and...

Page 320: ...amplitudes since the per unitized delta side has 3 relation amplitude difference to star connected side IL1DS LV IL1LV IL2LV 3 IL2DS LV IL2LV IL3LV 3 IL3DS LV IL3LV IL1LV 3 This is the so called vecto...

Page 321: ...Now this is again up to the user which way the signals are wanted to be shown it is possible also to negate the CTs currents when the subtract mode can be used for differential calculation and the bot...

Page 322: ...nt the bias current calculated Figure 1 1 1 4 155 Differential function characteristic biased and non biased In the characteristics the red line presents the allowed differential current in percentage...

Page 323: ...ight line which represents the transformer normal operation created differential current This part takes into account measurement errors transformer possible tap changer load side caused current varia...

Page 324: ...y REm Tap changer on load side TCE Possible auxiliary transformer or auxiliary winding which currents are not measured separately AUTE Transformer core magnetizing current TME Safety margin SME Now ho...

Page 325: ...n and calculate the maximum effect to worst side border Figure 1 1 1 5 157 Tap changer principle Generally tap changer means that the transformer transformation ratio can be adjusted in order to recei...

Page 326: ...rmers primary inductance is not known then can be used conservative estimate of 3 for the transformer magnetizing effect SME For conservative settings up to 5 safety margin is used typically Now we ha...

Page 327: ...CTEsec TCE CTEsec TCE 1 TCE 100 2 REm AUTE TME SME 36 Now this basic sensitivity is taking account the starting situation with no load to Turnpoint 1 in the characteristics Next thing is to decide whe...

Page 328: ...e 1 is calculated by using the transformer and CT nominal values in the maximum full load Turnpoint 2 of the transformer with highest possible differential current causing tap position Generally Slope...

Page 329: ...e ways to use biasing calculation and in practice one way to calculate differential current even there are add and subtract modes the effect will be the same since the differential current shall basic...

Page 330: ...will not be applicable even there is in zone fault on single end Now when thinking the possible situation when feeding is from HV side and the differential current is directly the fault feeding end c...

Page 331: ...ation IHVMAX I3phSCHV CTHVPRI 2332A 150A 5A 77 7ASEC 20 18 xIn ILVMAX I3phSCHV LV CTLVPRI 23327A 1200A 5A 97 2ASEC 20 2 xIn This is now the theoretical maximum of the current flowing in the CTs when b...

Page 332: ...A secondary instead of 5A all burdens will drop to level smaller to portion of 5A2 e g 1 25 Now normally copper cables are used to connect CTs to relay anyway in below table is presented also Aluminum...

Page 333: ...e should be 1 3 times the distance between of relay and CTs Next loading factor is the resistance of the relay measuring input In NP900 relays it is 0 0005 for current input This gives about 0 001VA w...

Page 334: ...LV sides are made with 4 mm2 wires HV side 150 5A 10P10 5VA ALFRATED 10 SRated 5VA SCTRN INS 2 CTRS 52 A 0 05 1 25VA RWire 10m 1 3 0 00508 m 0 066 SActual INS 2 RWire RRelay 52 A 0 066 0 0005 1 65 VA...

Page 335: ...the found differential current shall be 50 of the maximum peak current typically If the setting should be according to theoretical maximum margin then 5 xIn margin should be considered for the instan...

Page 336: ...relay and when the transformer is feeding the load with nominal power the result should look like this with the example settings and transformer Four characteristics here present the setting variation...

Page 337: ...one type of transformer and its properties Very common variation in this kind of transformer is when the star side no matter HV or LV or both is grounded thus forming a route outside of the Different...

Page 338: ...ulated zero sequence current from the per unitized currents before differential calculation thus negating the outside earth fault effect Figure 1 1 1 6 160 Correctly selected transformer setting preve...

Page 339: ...side of the transformer and also because of normal phase differential protection cannot be set to provide maximum sensitivity to inside area single phase earth faults due to transformer and applicati...

Page 340: ...fferential stage the reference current for the REF protection for transformers is always the protected side nominal current HV LV which is calculated in the relay TRF module For transformer applicatio...

Page 341: ...the single phase overcurrent fault is over this value set Turnpoint 2 to that value Slope 2 Set to maximum restraint calculation mode to 100 and average mode to 200 1 1 1 8 BLOCKINGS FROM HARMONICS 2N...

Page 342: ...properties the flux shall be 90 degrees behind the winding voltage and the system is in steady state This start up transition in the transformer effects so that the flux in the first half cycle after...

Page 343: ...rrents peak and FFT values as mentioned in the earlier chapter the calculated FFT value is about 50 of the peak value third graph presents the 2nd harmonic absolute values in amperes fourth graph pres...

Page 344: ...ed that the fundamental component currents which are used for differential calculations magnitudes are roughly as follows IL1peak 140 A 1 2xIn IL2peak 75 A 0 65xIn IL3peak 70 A 0 60xIn When rememberin...

Page 345: ...will increase significantly In this example the harmonic blocking limit was set to 15 ratio of 2nd harmonic fundamental per each phase which seems more than sufficient for this transformer and the pi...

Page 346: ...former magnetizing inrush currents As conservative setting suggestion for standard type transformer could be recommended 2nd harmonic blocking enabled with sensitivity set to around 15 20 harmonic con...

Page 347: ...mentioned cases the differential relay should not trip even the measured currents shall be considerably higher on the primary side than secondary side due to the over excitation in the transformer cor...

Page 348: ...is seen only in the primary side of the transformer and is seen by differential relay as pure differential current In the last graph is seen the differential pick up setting reached in situation when...

Page 349: ...be used it automatically blocks with smaller overvoltage in order if there is any differential current and releases if the overvoltage is too heavy when the differential current most probably is over...

Page 350: ...sed functions as well as the 2nd and 5th harmonic blocks activation signals These signals can be used in the protection application 1 1 1 10 SETTINGS AND SIGNALS Settings of the differential function...

Page 351: ...50Hz Info Transformer nominal frequency Used for calculation of transformer nominal short circuit inductance Transf Vect group 0 Manual 1 Yy0 2 Yyn0 3 YNy0 4 YNyn0 5 Yy6 6 Yyn6 7 YNy6 8 YNyn6 9 Yd1 10...

Page 352: ...election for LV side leads or lags LV side Selection is visible only if vector group is set to 0 Manual set HV LV side phase angle 0 0 360 00 deg 0 1de g 0 0deg TRF DIFF Angle correction factor for HV...

Page 353: ...rnpoint 1 0 01 50 00xIn 0 01xIn 1 00xIn Turnpoint 1 for the differential characteristics Slope 1 0 01 250 00 0 01 10 00 Slope1 of the differential characteristics Turnpoint2 0 01 50 00xIn 0 01xIn 3 00...

Page 354: ...acteristics Setting is visible only if Enable I0d REF HV side is set to 1 Enabled LV I0d Pickup 0 01 100 00 0 01 10 00 Base sensitivity for the LV side restricted earthfault differential characteristi...

Page 355: ...earth fault Bias current LV I0d Diff current Calculated LV side restricted earth fault Differential current LV I0d Char current Calculated LV side restricted earth fault differential current allowed w...

Page 356: ...V I0d Block Off 4558 71 DIF1 14 HV I0d Trip On 4559 71 DIF1 15 HV I0d Trip Off 4560 71 DIF1 16 LV I0d Block On 4561 71 DIF1 17 LV I0d Block Off 4562 71 DIF1 18 LV I0d Trip On 4563 71 DIF1 19 LV I0d Tr...

Page 357: ...1 220 Register content continued LV I0d Bias current LV I0d Differential current LV I0d Characteristics current SG in use Ftype Registered LV side REF Bias current Registered LV side REF Diff current...

Page 358: ...factor either from linear approximation or settable 10 point thermal capacity curve 1 Thermal heating time constant of the protected object in minutes 2 Thermal heating time constant of the protected...

Page 359: ...roportional to temperature rise caused by current squared This usually is the case with cables and objects while overhead lines heat dissipation is dependent of current weather conditions Weather cond...

Page 360: ...temperature can be set in C or F tmax Maximum temperature can be set in C or F for the protected object kmax Ambient temperature correction factor for the maximum temperature tmin Minimum temperature...

Page 361: ...ic consists of input magnitude processing thermal replica comparator block signal check and output processing Inputs for the function are setting parameters and measured and pre processed current magn...

Page 362: ...ting 0 Disabled Not in use Temp C or F deg 0 C 1 F 0 C Selection whether the temperature values of the thermal image and RTD compensation are shown in Celsius or Fahrenheit degrees Table 3 5 3 2 223 T...

Page 363: ...tref kamb 1 0 60 500 deg 1 deg 15 deg Temperature reference setting In this temperature manufacturer presumptions apply and the thermal correction factor is 1 00 rated temperature For ground dug cabl...

Page 364: ...it and Trip signals Table 3 5 3 3 225 Pick up characteristics setting SG selectable Name Range Step Default Description Enable TT Alarm 1 0 Disabled 1 Enabled 0 Disabled Enabling Disabling of the Alar...

Page 365: ...ssioning phase of the stage by software switch signal when relay common and global testing mode is activated User settable variables are binary signals from the system Blocking signal needs to reach t...

Page 366: ...for the object 2 Timing status TT Trip delay remaining Time to reach 100 theta TT Trip time to rel Time to theta to reach under trip limit when cooling TT Alarm 1 time to rel Time to theta to reach u...

Page 367: ...a Ref T current Active meas current T at the moment Max temp rise allowed Temp rise at the moment Hot Spot estimate Hot spot max all Trip delay rem Used SG dd mm yyyy hh mm ss mss 4288 4297 Descr seco...

Page 368: ...is set in the SGS function block which after all available functions enable corresponding setting groups If setting group is not activated but is tried to control on with SGS an event of failed setti...

Page 369: ...for all setting groups e g if setting group 2 is selected with signal and when it is released the setting group 1 shall not be automatically selected and the logic needs separate control to set the ac...

Page 370: ...ither enabled or disabled This setting has to be active before the setting group can be changed remotely or from local HMI This parameter is overriding local control of the setting groups and is not t...

Page 371: ...lse or steady state signals If steady state signal is applied no lower priority than SG1 SG2 and SG3 requests shall be processed Setting group 5 0 Not active 1 Active 1 0 Setting group 6 selection fou...

Page 372: ...uested 1 4175 65 SGS 15 SG2 Requested 1 4176 65 SGS 16 SG3 Requested 1 4177 65 SGS 17 SG4 Requested 1 4178 65 SGS 18 SG5 Requested 1 4179 65 SGS 19 SG6 Requested 1 4180 65 SGS 20 SG7 Requested 1 4181...

Page 373: ...the state of the Petersen coil connection the setting group control can be applied either with 1 wire or 2 wire connection depending of the application requirements In case of 1 wire connection is al...

Page 374: ...Series 374 504 A996A Figure 3 6 1 3 175 Setting group control with 2 wire connection from Petersen coil status Figure 3 6 1 3 176 Setting group control with 2 wire connection from Petersen coil statu...

Page 375: ...can be programmed to be used for in the setting group selection logic As can be seen from these presented examples the setting group selection with application control has to be built fully when using...

Page 376: ...rol logic control monitor and output handler In addition of these main parts in the object control block can be added object related CBFP and object wear monitor For the basic version of the object co...

Page 377: ...Link to the physical binary input Monitored object CLOSE status 1 means active close state of the monitored object Position indication can be done among binary inputs and protection stage signals by...

Page 378: ...cation requirements Table 3 6 2 1 235 Command digital signal inputs used by the OBJ function Signal Range Description Objectx Local Close control input DI1 DIx Local Close command from physical digita...

Page 379: ...cart position indication of the CB object ready use synchrocheck and control timings are available The functionality of the selected object is presented in the table below Table 3 6 2 2 237 Object ty...

Page 380: ...ready or not in use Ready timeout 0 000 1800 000 s 0 02 s 0 20 s Setting for ready wait timeout If the object ready is not received during this set time the close command will be rejected with error...

Page 381: ...2 3 180 Example of interlock application Closed earthing switch interlocks CB close Blocking signal has to reach the function 5 ms before control command in order it is received in time 3 6 2 4 EVENTS...

Page 382: ...15 Close Fail 1 2960 46 OBJ1 16 Close Request Off 0 2961 46 OBJ1 17 Close Command On 1 2962 46 OBJ1 18 Close Command Off 0 2963 46 OBJ1 19 Status Change On 1 2964 46 OBJ1 20 Status Change Off 0 3009 4...

Page 383: ...J3 19 Status Change On 1 3092 48 OBJ3 20 Status Change Off 0 3137 49 OBJ4 1 Object Intermediate 1 3138 49 OBJ4 2 Object Open 1 3139 49 OBJ4 3 Object Close 1 3140 49 OBJ4 4 Object Bad 1 3141 49 OBJ4 5...

Page 384: ...BJ5 18 Close Command Off 0 3219 50 OBJ5 19 Status Change On 1 3220 50 OBJ5 20 Status Change Off 0 In the register of the OBJ function is recorded statuses commands etc On event process data In the tab...

Page 385: ...yy hh mm ss mss StatusChangedOn dd mm yyyy hh mm ss mss ObjectIntermediate dd mm yyyy hh mm ss mss ObjectClose dd mm yyyy hh mm ss mss CloseCommandOff As can be seen the registers complement the event...

Page 386: ...xample connection of synchrocheck function in 3LN U4 mode when the SYN1 stage is in use and UL1 is the reference voltage Figure 3 6 3 2 Example connection of synchrocheck function in 2LL U3 U0 mode wh...

Page 387: ...Application Guide NP900 Series 387 504 A996A Figure 3 6 3 3 Example connection of synchrocheck function in 2LL U3 U4 mode when the SYN3 stage is in use and UL12 is the reference voltage...

Page 388: ...Application Guide NP900 Series 388 504 A996A Figure 3 6 3 4 Example application of synchrocheck over one breaker in 3LL and 3LN VT connection situations...

Page 389: ...Application Guide NP900 Series 389 504 A996A Figure 3 6 3 5 Example application of synchrocheck over one breaker with 2LL VT connection...

Page 390: ...Application Guide NP900 Series 390 504 A996A Figure 3 6 3 6 Example application of synchrocheck over two breakers in 2LL U3 U4 mode Reference of the U3 or U4 voltages may be U12 U23 or U31...

Page 391: ...es Obviously all of these three aspects are never exactly the same so it is needed to set the maximum difference between the measured voltages Outputs of the function are Syn Ok Bypass and Blocked sig...

Page 392: ...nt values are used for the function block Function block utilizes always peak to peak measurement from samples and the monitored magnitude is fundamental frequency RMS values Table 1 1 1 12 241 Analog...

Page 393: ...mmon and global testing mode is activated User settable variables are binary signals from the system 1 1 1 14 SETTING PARAMETERS Table 1 1 1 14 242 General settings of the synchrocheck function Name R...

Page 394: ...ce between the systems SYN freq diff 0 00 0 50 Hz 0 01 Hz 0 1 Hz Maximum allowed frequency difference between the systems NOTE Remember to set a voltage channel U3 or U4 into synchrocheck mode in the...

Page 395: ...6 SYN2 Ok On 1 0 2897 45 SYN1 17 SYN2 Ok Off 0 0 2898 45 SYN1 18 SYN2 Bypass On 1 0 2899 45 SYN1 19 SYN2 Bypass Off 0 0 2900 45 SYN1 20 SYN2 Volt condition OK 1 0 2901 45 SYN1 21 SYN2 Volt cond not ma...

Page 396: ...hall be locked from closing until the cause of the fault is repaired in the actual fault location Also close short circuit faults should avoid the autoreclosing to be even initiated in order to avoid...

Page 397: ...and how long dead times should be set for the reclosing scheme and also which protection functions should init the autorecloser Minimum times for the Dead Time setting is mostly dependent of the volta...

Page 398: ...short cable connection from substation to the overhead line and relatively long overhead line which typically ends to consumer The overhead line part can feed from basically any location residential f...

Page 399: ...se the breaker Manual reset can be applied from SCADA or locally from the HMI of the IED Following graphs present the principle signaling of the autorecloser in different cases possible for this type...

Page 400: ...shot is set for this scheme Figure 3 6 4 3 184 Settings for earth fault reclosing with two shots When Trip signal is used for the autorecloser cycle init then no additional starting or discrimination...

Page 401: ...next which is allowed for REQ2 input and Shot2 Running signal is set to active and Shot1 Running is drop off 7 Circuit breaker is opened and I0Dir Trip signal is released and simultaneously REQ2 sign...

Page 402: ...evious example with same settings and signals In this example fault persist for the high speed autoreclosing but is cleared by time delayed autoreclosing Figure 3 6 4 4 186 Settings for earth fault re...

Page 403: ...ble Shot for this request Shot2 is next which is allowed for REQ2 input and Shot2 Running signal is set to active and Shot1 Running is drop off 7 Circuit breaker is opened and I0Dir Trip signal is rel...

Page 404: ...P WITH TWO SHOT HIGH SPEED SUCCEEDS The Scheme for autoreclosing starter and shots is the same than in the previous examples with same settings and signals In this example fault is cleared by the high...

Page 405: ...is released Recloser starts to calculate the Shot1 Dead Time for closing the breaker 4 Dead Time for Shot1 is exceeded and autorecloser sends close request for the Object breaker the close conditions...

Page 406: ...OSING SEQUENCE FROM START WITH TWO SHOT FAILURE For this overcurrent autoreclosing scheme was set non directional overcurrent protection Start signal to operate as REQ1 starter which was enabled to Sh...

Page 407: ...REQ1 signal for autorecloser is released Recloser starts to calculate the Shot1 Dead Time for closing the breaker 4 Dead Time for Shot1 is exceeded and autorecloser sends close request for the Object...

Page 408: ...ecloser will jump to next available Shot for this request For this scheme is not anymore available shots so autorecloser initializes Final Trip state and drops AR Running Shot2 Running and REQ1 Runnin...

Page 409: ...0 ms for Shot 1 is elapsed and the autorecloser enters to running mode and sends open command to the breaker 3 Circuit breaker is opened and I Start signal is released and simultaneously REQ1 signal f...

Page 410: ...re reset and Reclaim Time for the Autorecloser application starts Difference in between of the autoreclosing and shot specific reclaim times is that if fault is returning in shot specific reclaim time...

Page 411: ...nal is activated simultaneously with corresponding starting time even the autorecloser is still in not running mode 2 Start time 500 ms for Shot 1 is elapsed and the autorecloser enters to running mod...

Page 412: ...d Recloser function will skip all timers set to 0 Also is possible to set the AR Reclaim not to be used after successful reclosing cycle 7 Autoreclosing Reclaim Time is exceeded and Autorecloser is se...

Page 413: ...nected the basic principles of autoreclosing can be applied for the overhead line as described previously This same principle should apply for any ring or meshed network where in the same line power c...

Page 414: ...maintained after reclosing to the fault Time required for mechanical IDMT relay to reset may be even 10 s in some cases When short dead times are required the relays should reset almost instantaneousl...

Page 415: ...block diagram of the AR function Figure 3 6 4 11 197 Simplified function block diagram of the AR function As can be seen in the function block diagram the autorecloser is tightly dependent of the obj...

Page 416: ...ed data and also output signals which can be configured to any output or logical input in the device If network configuration is changed during the autoreclosing sequence the operation of the autorecl...

Page 417: ...nary signal in the IED Reclosing request 4 fourth highest priority request which overrules all lower priority requests for autoreclosing When this request signal is activated and other conditions for...

Page 418: ...nd this signal is activated Signal can be connected to any relay IO as well as into communication protocols AR Locked When autorecloser is Locked mode this signal is activated Signal can be connected...

Page 419: ...uired General reclaim 0 Only shot reclaim 1 Shot reclaim and general reclaim 8 Selections if autorecloser runs after successful reclose including shot reclaim time the general reclaim object close rec...

Page 420: ...tep of 0 005 8 Shotx Dead Time delay This setting defines the breaker open time before autorecloser closes the breaker Time calculation starts from breaker open signal This selection can be changed dy...

Page 421: ...or example of the reading of the settings AR1 request is started by I Start signal and AR2 is started by I0Dir Trip signal Timings for AR1 is 500ms starting time followed by 200ms Dead time which afte...

Page 422: ...wn o General reclaim time is running o AR is locked When AR is in inhibit state it will recover to ready state when the reason for the inhibition is removed Lock out reasons for autorecloser are follo...

Page 423: ...ble AR timer value in Tools Events and logs Alarm events After this click Set button 3 6 4 17 EVENTS AND REGISTERS The AR function generates events and registers from the status changes of monitored s...

Page 424: ...3 Object Open Request 4046 63 AR1 14 Inhibit condition On 4047 63 AR1 15 Inhibit condition Off 4048 63 AR1 16 Locking condition On 4049 63 AR1 17 Locking condition Off 4050 63 AR1 18 Reserved 4051 63...

Page 425: ...rately Table 3 6 4 17 250 Register content Date Time Event code Timer value Used SG Inhibit reason on Inhibit reason off Locked reason on Locked reason off Status code Timer on AR registers are treate...

Page 426: ...2944 OBJ1 Object Intermediate dd mm yyyy hh mm ss mss 2946 OBJ1 Object Close dd mm yyyy hh mm ss mss 2961 OBJ1 Close Command Off dd mm yyyy hh mm ss mss 4087 AR1 Shot Reclaim Time On As can be seen th...

Page 427: ...closer function 3 6 5 COLD LOAD PICK UP CLPU 68 Cold load pick up function CLPU is used for detecting the so called cold load situations which relate to the distribution feeder protection after servic...

Page 428: ...source The operational logic consists of input magnitude processing threshold comparator block signal check time delay characteristics and output processing Inputs for the function are setting parame...

Page 429: ...ation of the CLPU function is controlled by ILow IHigh and IOver setting parameters which defines the maximum and minimum allowed measured current before action from the function The function constant...

Page 430: ...has been activated before blocking signal it will reset and the release time characteristics are processed as in case of when pick up signal is reset From blocking of the function a HMI display event...

Page 431: ...rush situation this parameter may be used to prolong the CLPU time over the first inrush Also this parameter operates as reclaim time for the CLPU function in case the inrush current is not immediatel...

Page 432: ...he measured current is below the ILow setting the Tset parameter can be set to lower value and even to 0 000s delay for immediate operation Figure 3 6 5 4 202 Example of timers and pick up parameters...

Page 433: ...start to count until Tmax time In this example the measured current is over the set IHigh setting until Tmax time and causes the release of the CLPU signal Figure 3 6 5 4 204 Example of timers and pi...

Page 434: ...g the Tmax timer is started CLPU signal will stay active until the Tmax time is used or the start up is over and Tmin time is over 3 6 5 5 EVENTS AND REGISTERS The CLPU function generates events and r...

Page 435: ...arting time Recl time Used SG dd mm yyyy hh mm ss mss 2688 2699 Descr Phase currents on trigger time Time remaining befor CLPU is active Time CLPU has been active before starting recorded starting tim...

Page 436: ...nputs are Initiating Blocking Setting group selection and Function trigger inputs The function can be initiated from digital input or circuit breaker close command connected to the Init input and the...

Page 437: ...will be activated Name Range Step Default Description Release time for SOTF 0 000 1800 000s 0 005 s 1 000 s SOTF active time after triggering 3 6 6 3 FUNCTION BLOCKING SOTF function can be blocked by...

Page 438: ...hange load power factor change transmission system variations R and X of the load changes and LTC changes From these mentioned quantities the LTC change Aim of using automatic voltage regulator is to...

Page 439: ...is monitored with mA measurement Tap changer position can be controlled with automatic control and manual control AVR monitors bus phase to phase voltage Operation of the AVR can be blocked by extern...

Page 440: ...lete phase to phase or phase to ground voltages left side connection example 3LN U4 also 3LL U4 and 2LL U3 U4 modes AVR measurement voltage can be selected directly to U12 U23 or U31 In case only one...

Page 441: ...nd calculations from the AVR function as well as the location of the tap changer at the moment Information about the settings and AVR status is found in this part Control settings Control settings inc...

Page 442: ...ow request the minimum time between pulses is used after the control pulse is terminated to prevent new control pulse output during this time Tap settings The properties of the used tap changer are se...

Page 443: ...ing group The target voltage and the control window where the voltage should be kept needs to be set for the voltage regulation AVR in percentage of nominal value On parameterization of the voltage wi...

Page 444: ...two and set to the U setting UTGT and U setting UTGT parameters If both of the window settings are set equally AVR has same sensitivity for over and undervoltage situations Voltage windows as well as...

Page 445: ...fect Voltage regulator reaches the set target window with one tap change However the voltage after tap change is very near to opposite limit If voltage changes back to original value tap change is nee...

Page 446: ...ration with definite set operating time on small deviations Typically this operating time may be 30 120 seconds Operating time starts to count when the measured voltage exceeds either U or U setting l...

Page 447: ...time for the second fast window U window is recommended have in inverse mode though it can also be set to definite operating mode This means that if the measured voltage exceeds the threshold a lot th...

Page 448: ...8 504 A996A Figure 3 6 7 1 214 Inverse operating time characteristics for second U window 1T Inverse operating time controls voltage back to the set target window faster if the deviation is bigger and...

Page 449: ...he set target voltage From the operating characteristics it can be seen that the faster inverse operation until the U window threshold setting which after U window threshold gives definite operating t...

Page 450: ...e characteristics calculate the consecutive time delays until the desired target window is reached Figure 3 6 7 1 216 Instant low command utilized in addition to two time delayed windows Pick up setti...

Page 451: ...tting effect to time characteristics AVRs low voltage blocking prevents the operation of the tap changer control in case of heavy short circuit faults in the feeding network side as well as the drifti...

Page 452: ...ration is to make sure that load side overcurrent short circuit fault does not cause tap change operation due to load side voltage drop If the operation of AVR is not blocked during the short circuit...

Page 453: ...60 General settings parameters Name Description Range Step Default Voltage measurement Selection of the measured system voltage from the U1 U2 and U3 inputs 0 U12 1 U23 2 U31 3 U4 input 0 U12 U4 measu...

Page 454: ...01 Un 100 Un Voltage set now to Based into tap changer location displays primary voltage deviation 50000 50000Vpri 0 01V 0 00V U instant setting Set instant stage compared to nominal 100 level 0 000 1...

Page 455: ...here as well Table 3 6 7 4 262 Control settings parameters Name Description Range Step Default Control mode Selection of control mode 0 Auto 1 Manual 0 Auto Manual tap increase Increase tap by 1 step...

Page 456: ...esenting the minimum tap position 0 000 4 000 mA 0 001mA 4 000mA mA input high range mA input measurement presenting the maximum tap position 0 010 20 000 mA 0 001mA 4 000mA Table 3 6 7 5 264 Tap sett...

Page 457: ...ation increases cumulative sum by 1 1 0 AVR overcurrent blocked How many times AVR operation has been blocked by detected overcurrent condition One blocking operation increases cumulative sum by 1 1 0...

Page 458: ...ode then this is the inverse operating time multiplier 0 000 1800 000s 0 005s 60 000s U instant in use Selection whether the instant low function is used 0 Not in use 1 In use 0 Not in use U setting U...

Page 459: ...d the AVR is counting time to tap change operation AVR U started Indicates that the second voltage window threshold has been exceeded and the AVR is counting time to tap change operation AVR outputs b...

Page 460: ...ommand Off 0 0 7364 115 VRG1 4 Block operation On 1 0 7365 115 VRG1 5 Block Operation Off 0 0 7366 115 VRG1 6 Block Output commands On 1 0 7367 115 VRG1 7 Block Output commands Off 0 0 7368 115 VRG1 8...

Page 461: ...ction utilizes total of eight separate setting groups which can be selected from one common source Also the operating mode of the CTS can be changed by setting group selection The operational logic co...

Page 462: ...tion block diagram of the CTS function Figure 3 7 1 219 Simplified function block diagram of the CTS function 3 7 1 1 MEASURED INPUT VALUES Function block uses analog current measurement values Functi...

Page 463: ...nted with 20 ms averaged history value from 20 ms of Start or Trip event Table 3 7 1 1 272 Residual current input signals selection Name Range Step Default Description I0 Input 0 Not in use 1 I01 2 I0...

Page 464: ...two other are 1 00 xIn Isum difference 0 01 40 00 x In 0 01 x In 0 10 x In Pick up ratio threshold for calculated residual phase current to measured residual current If the measurement circuit is heal...

Page 465: ...imum of 5 ms before the set operating delay has passed for blocking to be active in time 3 7 1 4 OPERATING TIME CHARACTERISTICS FOR TRIP AND RESET This function supports definite time delay DT For det...

Page 466: ...as been spent CTS will issue alarm Figure 3 7 1 5 222 System in case when primary circuit fault is found in phase L1 wiring Distinction in between primary and secondary fault in this case is impossibl...

Page 467: ...also if the fault current exceeds the Iset high setting Figure 3 7 1 5 224 System in case of low current and heavy unbalance If all of the measured phases magnitudes are below the Iset Lowlimit settin...

Page 468: ...ded the sum current and residual current are compared against each other and the wiring condition can be verified Figure 3 7 1 5 226 System in case when secondary phase current wiring is broken When p...

Page 469: ...icate primary side fault Figure 3 7 1 5 228 System in case of primary side high impedance earth fault In case of high impedance earth fault the CTS will not activate if the measurement conditions are...

Page 470: ...the CTS function is recorded activated blocked etc On event process data In the table below is presented the structure of CTS function register content This information is available in 12 last recorde...

Page 471: ...ment of voltage UL3 V 5 ms U1P Positive sequence voltage 5 ms U2N Negative sequence voltage 5 ms UZ0 Zero sequence voltage 5 ms UL12Ang Fundamental angle of UL12 voltage 5 ms UL23Ang Fundamental angle...

Page 472: ...he pick up is immediate when the monitored signal is activated Voltage transformer supervision can also report several different states of the measured voltage These can be seen in the INFO page of th...

Page 473: ...n event buffer is possible to select status On or Off messages In the function is available 12 last registers where the triggering event of the function ALARM activated or blocked is recorded with tim...

Page 474: ...e recorder supports 96 digital channels simultaneously with measured 9 analog channels The recorder provides great tool to analyze the performance of the power system in network disturbance situations...

Page 475: ...o sequence voltage U0 or synchrocheck voltage USS 8 16 32 64 s c U4 Zero sequence voltage U0 or synchrocheck voltage USS 8 16 32 64 s c Possible digital channels vary according the IED type All digita...

Page 476: ...ms Sec Pos seq curr 5ms Sec Neg seq curr 5ms Sec Zero seq curr 5ms Pri Pos seq curr 5ms Pri Neg seq curr 5ms Pri Zero seq curr 5ms Pos seq curr angle 5ms Neg seq curr angle 5ms Zero seq curr angle 5ms...

Page 477: ...s U3Volt TRMS p u 5ms U3Volt TRMS pri 5ms U3Volt TRMS sec 5ms U4Volt TRMS p u 5ms U4Volt TRMS pri 5ms U4Volt TRMS sec 5ms Pos seq Volt p u 5ms Pos seq Volt pri 5ms Pos seq Volt sec 5ms Neg seq Volt p...

Page 478: ...racked F CHB 5ms Tracked F CHC 5ms DI1 Dix 5ms Logical Output 1 32 5ms Logical Input 1 32 5ms Internal Relay Fault active 5ms Stage START signals 5ms Stage TRIP signals 5ms Stage BLOCKED signals 5ms C...

Page 479: ...ecording size For example in case that analogue channels IL1 IL2 IL3 I01 UL1 UL2 UL3 and U0 are selected sample rate is 64 s c and recording length is set to 1 0 seconds the IED has memory for 623 rec...

Page 480: ...y is full Keep olds won t accept new recordings when the memory is full Analog channel samples 0 8 s c 1 16 s c 2 32 s c 3 64 s c 3 64s c Sample rate of the disturbance recorder Samples are saved from...

Page 481: ...memory size and following settings Recording length 1 0 second Analog channel samples 32s c Analog recording channel 1 2 3 4 6 7 and 8 are used and Recorder digital channels is taking samples of trac...

Page 482: ...is described in Tools Settings DR path SMARTviewer is launched from Disturbance recorder menu as well 3 7 3 5 HOW TO ESTIMATE THE MAX LENGTH OF TOTAL RECORDING TIME When the disturbance recorder setti...

Page 483: ...ple rate is 64s c all nine analog channels are used and 2 digital channels are recorded the result is the following 16076647 samples 50Hz 9 1 64 200Hz 2 496s Total sample reserve 16076647 is derived f...

Page 484: ...move them to the plotter In this example phase currents IL1 IL2 and IL3 are selected 2 To have another plotter choose blue plus key icon that can be found on top Note Add Plotter text appears when mov...

Page 485: ...s choose icon 2 that can be found on top Note Remove All Cursors text appears when moving mouse on top of the icon 3 Zoom in manually by going on top of any plotter and holding down mouse left Move mo...

Page 486: ...nterval combo box You have the option to choose will the measurements be recorded in SMART9 or in the relay itself with Record in dropdown box If you have chosen to record in SMART9 SMART9 software an...

Page 487: ...t and it monitors the three phase current values in the tripping opening moment The maximum interrupting life operations value per each phase are calculated from these currents which is cumulatively d...

Page 488: ...always uses the fundamental frequency magnitude of the current measurement input Table 3 7 5 1 284 Analogic magnitudes used by the CBW function Signal Description Time base IL1RMS Fundamental RMS mea...

Page 489: ...led Enabled Enable Disable selection of the Alarm 1 stage Alarm 1 Set 0 200000 operations 1 operation 1000 op Pick up threshold for remaining operations When the remaining operations is below this set...

Page 490: ...ces separately Table 3 7 5 5 288 Register content Date Time Event code Trigger current All Op ITrg Deduct Op Op Left dd mm yyyy hh mm ss mss 3713 3717 Descr Phase currents on trigger time Allowed oper...

Page 491: ...Application Guide NP900 Series 491 504 A996A 3 7 5 6 SETTING EXAMPLE...

Page 492: ...as the ratio of the sum of powers of all harmonic components to the power of fundamental frequency Harmonics can be caused by different sources in the electric networks like electric machine drives t...

Page 493: ...ed signals Setting parameters are static inputs for the function which are changed only by user input in the setup phase of the function THD function utilizes total of eight separate setting groups wh...

Page 494: ...RMS measurement of phase L3 C current 5 ms I01FFT Fundamental RMS measurement of residual I01 current 5 ms I02FFT Fundamental RMS measurement of residual I02 current 5 ms Selection of the THD calculat...

Page 495: ...urrent I02 The measured THD value has to be over this setting to activate the alarm signal The pick up activation of the function is not directly equal to start signal generation of the function Start...

Page 496: ...ion Tpha 0 000 1800 000s 0 005s 10 000s Delay time setting for the alarm timer from the phase currents measured THD TI01 0 000 1800 000s 0 005s 10 000s Delay time setting for the alarm timer from the...

Page 497: ...G dd mm yyyy hh mm ss mss 3521 3534 Descr Measured THD values on the trigger event Time left to Alarm on the trigger event 1 8 Event Number Event channel Event block name Event Code Description Event...

Page 498: ...e 3 7 7 1 9 User edited alarm descriptions User edited alarm text will be displayed in the Alarm view in the HMI when the alarm has been activated To update the user descriptions update the settings C...

Page 499: ...splayed in the Alarms display with continuously lit LED When the signal that has activated the alarm has already been disabled alarm will persist until it has been cleared in the HMI This kind of alar...

Page 500: ...be also triggered by other protections as well Function can be used if three phase current and three phase voltage have been connected to the relay In the configuration the triggering signals trigger...

Page 501: ...rix Then the function checks if phase to earth voltages are available If phase to earth voltages are not available fault locator can record only phase to phase impedance loops If phase to earth voltag...

Page 502: ...nt activates the function shall not process the situation further From blocking of the function a HMI display event as well as time stamped blocking event with information of the startup voltage value...

Page 503: ...nformation is available in 12 last recorded events Table 3 7 8 4 299 Register content Date Time Event code Fault type Fault direction Fault reactance Fault Current Fault Current Fault distance Setting...

Page 504: ...Application Guide NP900 Series 504 504 A996A A996A...

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