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TD_MRI1_06.05_GB 

31 

6.4.9  

Checking the external blocking and 

 reset 

functions 

 
The external blocking input inhibits e. g. the function of 
the high set element of the phase current. To test the 
blocking function apply auxiliary supply voltage to the 
external blocking input of the relay (terminals E8/D8). 
The time delay t

I>

 should be set to EXIT for this test. In-

ject a test current which could cause a high set (I>>) 
tripping. Observe that there is no trip and alarm for the 
high set element. 
 
Remove the auxiliary supply voltage from the blocking 
input. Inject a test current to trip the relay (message 
“TRIP” on the display). Interrupt the test current and ap-
ply auxiliary supply voltage to the external reset input 
of the relay (terminals C8/D8). The display and LED 
indications should be reset immediately. 
 
 

6.4.10   Test of the CB failure protection 

 
For testing the tripping time a test current of about 2 
times the rated current to be injected. The timer is 
started upon tripping of the relay of a protection func-
tion (I>, I>>, I

E

>, I

E

>>) and stopped as soon as the re-

lay for the CB failure protection has picked up. Mes-
sage "CBFP" is displayed. The tripping time ascer-
tained by the timer should not deviate more than 1% 
or, at short trip delay, less than 10 ms from the set 
tripping time. 
Alternatively, the timer can be started when the aux. 
voltage and the test current are injected simultane-
ously. The timer stops when the corresponding output 
relay for circuit breaker failure protection trips. 
In this case the previously measured tripping delay 
(see section 6.4.5) has to be subtracted from the total 
tripping time measured. 
 
 

6.5    Primary injection test 

 
Generally, a primary injection test could be carried out 
in the similar manner as the secondary injection test 
described above. With the difference that the pro-
tected power system should be, in this case, con-
nected to the installed relays under test “on line”, and 
the test currents and voltages should be injected to the 
relay through the current and voltage transformers with 
the primary side energized. Since the cost and poten-
tial hazards are very high for such a test, primary in-
jection tests are usually limited to very important protec-
tive relays in the power system. 

 
 

 
Because of its powerful combined indicating and 
measuring functions, the 

MRI1

 relay may be tested in 

the manner of a primary injection test without extra ex-
penditure and time consumption. 
In actual service, for example, the measured current 
values on the 

MRI1

 relay display may be compared 

phase by phase with the current indications of the 
ammeter of the switchboard to verify that the relay 
works and measures correctly. In case of a 

MRI1

 relay 

with directional feature, the active and reactive parts 
of the measured currents may be checked and the ac-
tual power factor may be calculated and compared it 
with the cos

ϕ

 -meter indication on the switchboard to 

verify that the relay is connected to the power system 
with the correct polarity. 
 
 

6.6   Maintenance 

 
Maintenance testing is generally done on site at regu-
lar intervals. These intervals vary among users depend-
ing on many factors: e.g. the type of protective relays 
employed; the importance of the primary equipment 
being protected; the user's past experience with the re-
lay, etc. 
For electromechanical or static relays, maintenance 
testing will be performed at least once a year accord-
ing to the experiences. For digital relays like 

MRI1

this interval can be substantially longer. This is be-
cause: 
 

• 

the 

MRI1

 relays are equipped with very wide self-

supervision functions, so that many faults in the relay 
can be detected and signalized during service. Im-
portant: The self-supervision output relay must be 
connected to a central alarm panel! 

• 

the combined measuring functions of 

MRI1

 relays 

enable supervision the relay functions during service. 

• 

the combined TRIP test function of the 

MRI1

 relay al-

lows to test the relay output circuits. 

 
A testing interval of two years for maintenance will, 
therefore, be recommended. 
During a maintenance test, the relay functions includ-
ing the operating values and relay tripping characteris-
tics as well as the operating times should be tested. 
 
 
 
 

Summary of Contents for HighTECH Line

Page 1: ...CTION TECHNOLOGY MADE SIMPLE DIGITAL MULTIFUNCTIONAL RELAY FOR TIME OVERCURRENT PROTECTION HighTECH Line DIGITAL MULTIFUNCTIONAL RELAY FOR TIME OVERCURRENT PROTECTION Revision A Original document Engl...

Page 2: ...for earth fault element tIE 5 2 14 Reset mode for inverse time tripping in earth current path 5 2 15 Current setting for high set element of earth fault supervision IE 5 2 16 Trip delay for high set...

Page 3: ...h fault protection E X Type 7 3 4 Earth fault protection ER XR Type 7 3 5 Switch failure protection 7 3 6 Interface parameter 7 3 7 Inverse time overcurrent protection relay 7 3 8 Direction unit for p...

Page 4: ...e measured values by using dis crete Fourier analysis to suppress the high frequence harmonics and DC components induced by faults or system operations Selectable protective functions between definite...

Page 5: ...the connection has to be realized as per Figure 3 1 and Figure 3 2 Figure 3 3 Phase current measuring and earth current detection by means of Holmgreen circuit This connection can be used with three...

Page 6: ...inally fed to the analog digital converter For the unit type with earth fault directional features ER XR relay type the residual voltage UE in the sec ondary circuit of the voltage transformers is int...

Page 7: ...t MRI1 To prevent that the C B trip coil circuit is interrupted by the MRI1 first i e before interruption by the C B auxiliary contact a dwell time is fixed This setting ensures that the MRI1 remains...

Page 8: ...X soli resi X X X tCBFP X X X X X X X X X X X 50 60 Hz X X X X X X X X X X X LED Flash X X X X X X X X X X X RS485 Slaveaddress X X X X X X X X X X X Baud Rate 3 X X X X X X X X X X X Parity Check 3...

Page 9: ...RESET ENTER TRIP t I I E CHAR I t E I I E tI E EARTH E RS E DISPLAY Figure 3 8 Front panel MRI1 E X SELECT RESET ENTER TRIP t I I CHAR I tI I tI PHASE MRI1 IR L1 L2 L3 RS Q I P I DISPLAY Figure 3 9 F...

Page 10: ...display At pickup trip and parameter setting the green LED lights up to indi cate the forward direction the red LED indicates the reverse direction The LED marked with letters RS lights up during sett...

Page 11: ...induced transients or other system dis turbances The calculated actual current values are compared with the relay settings If a phase current exceeds the pickup value an alarm is given and after the s...

Page 12: ...s at least 2 periods 40 ms at 50 Hz are evaluated For the MRI1 overcurrent relays with directional feature different time delays or time multipliers can be set for forward and backward faults ref to c...

Page 13: ...ing the relay Earth faults beyond the current transformers i e on the consumer or line side will not be detected Figure 4 4 Generator stator earth fault protetion 4 4 2 System earth fault protection W...

Page 14: ...n be measured in three different ways depending on the voltage transformer connec tions refer to Table 4 1 Total current can be measured by connecting the unit either to a ring core C T or to cur rent...

Page 15: ...e current for faulted and non faulted lines in case of compensated systems cos UE residual voltage IE zero sequence current IL inductive component of zero sequence current caused by Petersen coil IC c...

Page 16: ...earthed system are pre dominantly ohmic in character with a small inductive part The characteristic angle for these types of system has therefore been set at 170 in relation to the zero sequence volta...

Page 17: ...E changeover of isolated sin or compensated cos networks for ER XR type SIN COS SELECT RESET Change over of solidly resistance earthed networks SR type SOLI RESI SELECT RESET Switch failure protection...

Page 18: ...play The new setting value can then be changed by using push buttons If through a new setting another relay characteristic other than the old one has been chosen e g from DEFT to NINV but the time del...

Page 19: ...cedure for forward or backward faults described in chapter 5 2 3 is also valid for the trip ping time of the high set element 5 2 7 Relay characteristic angle RCA The characteristic angle for directio...

Page 20: ...rrents have dropped to 1 xIN within this time CB failure is detected and the related relay activated The CB failure protection function is deactivated again as soon as the phase currents have dropped...

Page 21: ...ignment mode is selected The relays are assigned as follows LEDs I I IE IE are two coloured and light up green when the out put relays are assigned as alarm relays and red as tripping relays In additi...

Page 22: ...R tripping X 1 _ _ _ tI red IE V alarm X _ _ _ 4 IE green tIE V tripping X 1 _ _ _ tIE green IE R alarm X _ _ _ 4 IE red tIE R tripping X 1 _ _ _ tIE red IE V alarm X _ _ _ 4 IE green tIE V tripping X...

Page 23: ...multiplier setting for inverse time overcurrent is a scale factor for the selected characteristics The characteristics for two adjacent relays should have a time interval of about 0 3 0 4 s High set e...

Page 24: ...indicate that it is not a current fault LEDs which were blinking blinking dur ing trip conditions element had picked up just briefly flash If the relay is still in trip condition and not yet reset TR...

Page 25: ...cond part of the soft ware version of the relay e g 4 01 The software version should be quoted in all correspondence Press ing the TRIP button once more the display shows PSW Please enter the correct...

Page 26: ...In By using an RMS metering instrument a greater deviation may be observed if the test current contains harmonics Be cause the MRI1 relay measures only the fundamental component of the input signals...

Page 27: ...o times IS The tripping time may be red from the characteristic curve diagram or calculated with the equations given under technical data Please observe that during the secondary injection test the te...

Page 28: ...directional feature of the relay and the current source is connected to phase 1 current input B3 B4 then the voltage source should be connected to relay terminals A5 A7 In order to test the directiona...

Page 29: ...to red Relay 2 drops and relay 3 responds This test must be repeated for current inputs 12 and 13 In order to determine the direction in the earth current circuit SR version refer to Fig 8 with the ch...

Page 30: ...ng a relay with earth fault directional feature one of the input energizing quantity voltage shall be applied to the relay with a constant value within its ef fective range The other input energizing...

Page 31: ...e current and voltage transformers with the primary side energized Since the cost and poten tial hazards are very high for such a test primary in jection tests are usually limited to very important pr...

Page 32: ...ly 4 x IN Thermal withstand in voltage circuit continuously 1 5 x UN 7 2 Common data Dropout to pickup ratio 97 Returning time 30 ms Time lag error class index E 10 ms Minimum operating time 30 ms Tra...

Page 33: ...01 0 02 0 05 0 1 0 2 5 from set value or 0 3 IN 3 or 20 ms 3 of the measuring value of the current or 20ms see EN60255 3 IE tIE 0 01 15 x IN EXIT 0 03 2 0 s EXIT 0 001 0 002 0 005 0 01 0 02 0 05 0 1 0...

Page 34: ...05 0 01x IN 0 01 0 02 0 05 0 1 x IN 0 01 s 0 02 s 0 05 s 5 from set value or 0 3 IN ER 0 03 IN XR 3 or 15 ms UE UN 100 V 3 PHA e n 1 70 V 1 1 1 120 V UN 230 V 3 PHA e n 2 160 V 1 1 2 300 V UN 400 V 3...

Page 35: ...at I 1 x IN Connection angle 90 Characteristic angle 15 27 38 49 61 72 83 Effective angle 78 related to relay characteristic angle at UN 7 3 9 Determination of earth fault direction MRl1 ER XR Measure...

Page 36: ...5 0 6 0 8 1 0 1 4 Figure 7 2 Extremely Inverse 1 2 3 4 5 6 7 8 910 20 I IS 0 1 1 10 100 1000 t s tI 10 0 8 0 6 0 4 0 3 0 2 0 0 05 0 1 0 2 0 3 0 4 0 5 0 6 0 8 1 0 1 4 Figure 7 3 Very Inverse 1 10 I IN...

Page 37: ...X Rated current 1 A in earth circuits 5 A 1 5 Housing 12TE 19 rack Flush mounting A D RS485 Alternatively with Modbus Protocol M Earth fault current relay with directional feature MRI1 R Earth curren...

Page 38: ...M Combinated time overcurrent and earth fault current relay with earth current directional feature MRI1 I R 3 phase measuring I I Rated current 1 A 5 A 1 5 Phase fault directional feature R Rated vol...

Page 39: ...X X 0 01 x IN E 0 1 IN X WARN TRIP X X X X X X TRIP CHAR IE X X X X X X DEFT tIE V tIE R X X X X X X X X X 0 05 s ER XR 0 04 s others 0s 60 s earth X X X X X X 0 s IE X X X X X X X X X 0 01 x IN E 0 1...

Page 40: ...y 4 Default setting Actual setting Default setting Actual setting Default setting Actual setting Default setting Actual setting I alarm V X tI tripping V X I alarm R X tI tripping R X I alarm V X t tr...

Page 41: ...IE X TCBFP X This technical manual is valid for software version D01 8 10 MRI1 ER IER IRER D20 2 00 MRI1 XR IXR IRXR D24 1 00 MRI1 X IX IXR D00 8 10 MRI1 I E IE IR SR IRE ISR IRSR Modbus Version numbe...

Page 42: ...D 47884 Kempen Germany Telephone 49 0 21 52 145 1 Internet www SEGelectronics de Sales Telephone 49 0 21 52 145 331 Fax 49 0 21 52 145 354 E mail info SEGelectronics de Service Telephone 49 0 21 52 14...

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