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Type KD-3 Relay

41-498B

27

THIS SPACE RESERVED FOR NOTES

Courtesy of NationalSwitchgear.com

Summary of Contents for KS

Page 1: ...or a completely offset circle characteristic with both the long reach and the short reach adjustable In KD relay applications where a normal second zone or third zone setting of the three phase unit might cause tripping because of possible load conditions the conventional relay settings must be shortened to exclude load The KD 3 displaced circle characteris tic may be added to the KD relay three p...

Page 2: ...oportional to the line current is subtracted vectorially from the relay terminal voltage The second section is connected to an adjustable loading resistor and provides a means of adjusting the phase angle relation between primary current and the induced secondary voltage The phase angle may be set for any value between 60 and 80 by adjusting the resistor between its minimum and maximum values resp...

Page 3: ...The electromagnet has two series connected coils mounted diametri cally opposite one another to excite each set of poles and two locating pins The locating pins are used to accurately position the lower pin bearing which is mounted on the frame with respect to the upper pin bearing which is threaded into the bridge The electromagnet is secured to the frame by four mounting screws The moving elemen...

Page 4: ... to the magnetic core upon energization of the switch When the switch closes the moving contacts bridge two stationary contacts completing the trip circuit Also during this operation two fingers on the armature deflect a spring located on the front of the switch which allows the operation indicator target to drop The target is reset from outside of the case by a push rod located at the bottom of t...

Page 5: ...age is then advanced 90 by the phase shifting action of capacitor Ccs to provide voltage ZY across the Z SR coils The resulting diagram has an X Y Z positive sequence pnase rotation which restrains the unit for this fault beyond the protected zone Using the same method of analysis for a fault at location B the long reach setting Z it is shown that X Y and Z lie in a straight line indicating equal ...

Page 6: ...ch compensators As shown in Figure 6 the Short Reach setting ZgR may be positive or negative with respect to ZgR or it may be zero depending upon the current circuit connections to the Short Reach compensator TQ The external schematic Figure 7 shows positive polarity current connections to both TA and TQ Solid line characteristics of Figure 6 are typical for a positive Z SR Memory action in the tr...

Page 7: ...ading resistor when connected is to produce an internal drop in the compensator which is out of phase with the induced voltage V is phase shifted to change the compensator maximum torque angle As a result of this phase shift the magnitude of V is reduced as shown in Figure 2 Tap markings in Figure 3 are based upon a 75 compensator angle setting If the resistors R2A and R2C are adjusted for some ot...

Page 8: ...1 Trip Circuit Constants 1 ampere rating 0 2 2 0 ampere rating 0 1 ohms d c resistance 0 2 tap 6 5 ohms 2 tap 0 15 ohms SETTING CALCULATIONS Relay reach is set on the tap plate shown in Fig 3 markings are The tap TA 1 3 1 74 2 4 3 3 4 5 6 3 8 7 TC 87 l 16 1 6 2 2 3 0 4 2 5 8 SA and Sc 1 2 3 MA and Mc 03 06 06 Values between taps Maximum torque angle is set for 75 current lagging voltage in the fac...

Page 9: ...s positive when L is above R and acts to Lower the Z setting The sign is negative when R is above L and acts to raise the Z setting Zpri ohms per phase of the line section to be protected Rc current transformer ratio Rv potential transformer ratio The following procedure should be followed in order to obtain an optimum setting of the relay Relate the general equation to Long Reach or Short Reach b...

Page 10: ...for the two auto transformer secondaries MA and Me All of these settings are made with taps on the tap plate which is located above the operating unit Figure 3 shows the tap plate Compensator TA and TQ Each set of compensator taps terminate in inserts which are grouped on a socket and form approximately three quarters of a circle around a center insert which is the common connection for all of the...

Page 11: ...for which an rM setting can be made are from 15 to 15 in steps of 03 The value of a setting is the sum of the numbers that are crossed when going from the R lead position to the L lead position The sign of the M value is determined by which lead is in the higher position on the tap plate The sign is positive if the L lead is higher and negative if the R lead is higher An M setting may be made in t...

Page 12: ...es on the flange for the semi flush type FT case Either the stud or the mounting screws may be utilized for grounding the relay The electrical connections may be made directly to the terminals by means of screws for steel panel mounting or to the terminal stud furnished with the relay for thick panel mounting The terminal stud may be easily removed or inserted by locking two nuts on the stud and t...

Page 13: ... between the bridging moving contact and the adjustable stationary contacts The bridging moving contact should touch both stationary contacts simultaneously ROUTINE MAINTENANCE The relays should be inspected periodically at such time intervals as may be dictated by experience to insure that the relays have retained their calibration and are in proper operating condition All contacts should be clea...

Page 14: ... The lower bearing position is fixed and cannot be adjusted Check to see that the taps on front of the tap block are set as follows TA set on 8 7 and TQ set on 5 8 SA and SQ set on 1 R for MA and L for MA and Mc hangs free Resistors R2A and R2C open circuited by adjustable bands not making contact A Compensator Angle Adjustment 1 Long Reach Compensator TA a Connect the relay as per Figure 12 Test ...

Page 15: ... should be equal to 100 l the sum of values between R and the tap being measured Example 100 1 t 03 06 109 volts Transformers which have an output different from nominal by more than 1 0 volt probably have been damaged and should be replaced C Tripping Unit Core Adjustment The adjustable core is set at the factory to bias the contacts open on current only This adjustment can be checked or made acc...

Page 16: ...t hand backstop screw the stationary contact in until it just touches the moving Then back the stationary contact out two thirds 2 3 of one turn to give 0 020 inch gap between contacts contact F Spring Restraint and Impedance Curve Connect for Test No 6 of Figure 12 Set TA 8 7 and TQ 3 0 SA and SQ 1 R for MA and MQ set 0 0 T for MA and MQ should be in the top positions 1 L Set 5 0 volts A 0 88 amp...

Page 17: ...an the particular ICS tap setting being used for the 0 2 2 ampere ICS The operation indicator target should drop freely The contact gap should be approximately 0 047 for the 0 2 2 0 ampere unit and 0 070 for the 1 ampere unit between the bridging moving contact and the adjustable stationary contacts The bridging moving contact should touch both stationary contacts simultaneously RENEWAL FARTS Repa...

Page 18: ... Inch Resistor 355 Ohms Fixed 2 Inch Resistor 600 Ohms Adjustable 4 MFD Capacitor Parallel Connected 1 8 MFD Capacitor Series Connected Variable Reactor Compensator primary Taps 1 3 1 74 2 4 3 3 4 5 6 3 3 7 Compensator Frimary Taps 87 1 16 1 6 2 2 3 0 4 2 5 8 Auto transformer primary Taps 1 2 3 Auto transformer Secondary Between Taps 0 0 03 06 06 VSR A R2A R2C CAP ccs x TA Tc SA Sc M Me Courtesy o...

Page 19: ...Type KD 3 Relay 41 498B 19 S M rA R2A REAR VIEW FRONT VIEW r Fig 1 Type KD 3 Relay Without Case Courtesy of NationalSwitchgear com ...

Page 20: ...ERATED SHORTING SWITCH REO HANDLE CURRENT TEST JACK TEST SWITCH TERMINAL FRONT VIEW T N V ADJUSTABLE ANGLE 185A348 i Fig 4 Internal Schematic of Type FT31 case ICS Coil Not Tapped for Relays with 1 Amp I C S 1 849A034 Fig 2 Compensator Construction SHORT REACH SETTINGS LONG REACH SETTINGS Z ZLR SR I LEAD L1 1 LEAD R Fig 3 Tap Plate Courtesy of NationalSwitchgear com ...

Page 21: ... e to Li _ Nl a N Z 0 I CD M J W J t UJ Nl n HI X o x UJ a CD z o o 2 H O J N CO N X o NJ c X l H LL t CD O Z NJ HI H M t LU K CO NJ M X o UJ O NJ N 2 O CO X CO o Nl 1 _ H O X IN O N UJ It 3 z T x x u I i I UJ CD I t M 03 O t NJ I 03 J H t a M I H I t 2 CO H UJ _i a x Nl u c z Q u z I X o UJ I CD M t I Nl t M I Nl Nl W Fig 5 Voltage and Current Conditions for the Type KD 3 Relay for Faults at Vari...

Page 22: ...AY ICS i K 0 3 R 21 21 2 FIG B DISTANCE CHARACTERIS TIC INTERSECTING ORIGIN D CO o KD 3 CURRENT CONNECTIONS AS SHOWN IN CHART 2 O O U u R 5 I o p p o u UJ UJ O Q 5 2 52 FIG C OISTANCE CHARACTERIS TIC INCLUDING ORIGIN T 0 a KO 3 CURRENT CONNECTIONS AS SHOWN IN CHART 52 I o o z z Q a a a TC I NEG 1 r r h ZiLRl JI 21 2 I DEVICE TC T 6 DEVICE 5 NO KO 3 CURRENT CONNECTIONS TIME R KD 3 RELAY CIR BKR AUX...

Page 23: ...SR 0 345 ZLR 8 8 cn o 120 120 7 i 7 2 LOCATION OF FAULT IN OF RELAY ZLR SETTING LOCATION OF FAULT IN OF RELAY ZLR SETTING 90 75 50 3 4 5 o o 100 100 6 6 90 75 50 34 5 A 5 5 2 80 80 v 2Z 2 7 4 4 UJ 5 60 60 A s 35 3 3 o V 40 40 K 2 2 cn UJ Q 20 20 I o 0 0 0 10 20 30 40 50 60 70 80 10 20 30 40 50 60 70 80 IZQLR l CURRENT TIMES LONG REACH IMPEDANCE SETTING 0 185A422 Fig 10 Typical Operating Time Curve...

Page 24: ...S l M 0 CURRENT CIRCUIT rl 5 AMPS 75 12 i TTT 1 i i 10 u t I t i m t VOLT AMPERES V 8 z f VARS rru 4 LU a cr WATTS CD 4 4 1 6 r m t 4 i I 1 2 TC rt t it 1 V I 0 4 30 5 8 Tc 87 1 16 1 2 2 a f A l 3 1 74 2 4 3 3 87 6 3 4 5 tA TC TAP SETTING 185A463 Fig 11 Type KD 3 Relay Burden Data Courtesy of NationalSwitchgear com ...

Page 25: ...I WATTMETER HJ MA OR AJ LOAD CD PHASE ANGLE METER W o VAR I ABLE AUTO TRANSFORMER NULL DETECTING VOLTMETERS O a AMMETER A a 3 CO n 10 o A B a 6 H U 1 0 INDICATING i O LAMP 5 6 7 O r H CD TEST CONNECT TO TERMINAL NO 6 7 V 5 LA LC ADJUST OO 1 IA 1B A Nc R H 2 A CD h 1 MA Nc R H 2 21 P 3 X FORMER CHECK H 1 4 CORE 0 15 15 5 H IA 15 15 X SPRING AND IMPEDANCE CURVE 15 15 6 H A 290B752 ...

Page 26: ... PANEL tM 9 II 2 H rr A Q 2 HOLES 16 t SPACE KS PCJZ THIN PANELS 100 i IQ SCREW FORTYMCK FWUEL USE 3 ie n uo 190 32 SCSEW F0R THICK P4N CL USE 90 3 S UD I I I I I z Si 32 i t T 1 2 t 0 i rn Uo r Lr JJU C lA 10 HOLES OR CUTOUT TERMINAL HUNi CR 4 i W A lT2 TERMINAL AND MOUNTING DETAILS PANEL DRILLING OR CUTOUT FOR PROTECTION MTG FRONT VIEW NOTEiALL D1KAEWSVONS VN INCH 57 D 7902 Fig 13 Outline Drilli...

Page 27: ...Type KD 3 Relay 41 498B 27 THIS SPACE RESERVED FOR NOTES Courtesy of NationalSwitchgear com ...

Page 28: ...A ABB Automation Inc 4300 Coral Ridge Drive Coral Springs Florida 33065 TEL 954 752 6700 FAX 954 345 5329 41 498B Type KD 3 Relay visit our website at www abbus com papd iliiw 1111 V Courtesy of NationalSwitchgear com ...

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