Phase Toc Element (51P); Iec Inverse Curve; Iec Very Inverse Curve; Iec Extremely Inverse Curve - GE MIFII GEK-106237P Instruction Manual

9 RELAY COMMISSIONING

9.15PHASE TOC ELEMENT (51P)

Available curves IEC, ANSI or IAC (Inverse, Very Inverse, Extremely Inverse, Inverse Short, Inverse Long) and the Definite
Time are tested with three points for each curve (one "no-trip point" and two "trip points"). This gives us a total of 12 points
for each protection element. Tests are carried out for different phases. Each point is tested with a different pick up and dial
in order to test the whole range of the relay.
Enable 51P element only, and set its current pickup value to the minimum possible.
Set the relay as follows:
Apply 0.9 times the pickup current into phase A and the relay should not trip.
Apply 1.5 times the pickup current and the relay should trip between 15.3 and 19.7 sec.
Apply 5 times the pickup current and the relay should trip between 4.0 and 4.6 sec.
Set the relay as follows:
Apply 0.9 times the pickup current into phase B and the relay should not trip.
Apply 1.5 times the pickup current and the relay should trip between 23.4 and 31.8 sec.
Apply 5 times the pickup current and the relay should trip between 3.2 and 3.6 sec.
Set the relay as follows:
Apply 0.9 times the pickup current into phase C and the relay should not trip.
Apply 1.5 times the pickup current and the relay should trip between 27 and 39 sec.
Apply 5 times the pickup current and the relay should trip between 1.5 and 1.8 sec.
GEK-106237P
51P SETTINGS GROUP
Curve MOD INVERSE
Time Dial 1
51P SETTINGS GROUP
Curve VERY INVERSE
Time Dial 1
51P SETTINGS GROUP
Curve EXTREMELY INVERSE
Time Dial 0. 5
MIFII Digital Feeder Relay
9.15 PHASE TOC ELEMENT (51P)

9.15.1 IEC INVERSE CURVE

9.15.2 IEC VERY INVERSE CURVE

9.15.3 IEC EXTREMELY INVERSE CURVE

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