Instantaneous Phase Overcurrent Timing Test; Instantaneous Ground Fault Overcurrent Timing Test; Phase Overcurrent Curve Verification; Ground Fault Overcurrent Curve Verification - GE 735 Instruction Manual

6 TESTING
Set the phase pickup dial to OFF. Set the phase instantaneous dial to the desired level. Using the 3-phase Test Set inject
current equal to or above the instantaneous level setting. The timer on the 3-phase Test Set should be setup to start when
current is injected and stop when the trip or auxiliary (if assigned) relay activates. Verify that the INST 50 phase A, B, or C
(whichever phase tested) LED has been activated and latched.
Set the ground pickup dial to OFF. Set the ground instantaneous dial to the desired level. Using the 3-phase Test Set inject
current equal to or above the instantaneous level setting. The timer on the 3-phase Test Set should be setup to start when
current is injected and stop when the trip and/or auxiliary relay (depending upon how assigned) activates. Verify that the
INST 50 N LED has been activated and latched.
Using the switches on the faceplate select the desired settings to test. i.e. pickup, curve shape and time multiplier. Set
instantaneous switch to OFF. From the option dip switches located on the side of the relay select the phase time multiplier
shift. If the curve type needs to be changed or checked this can be done through the setup program-setpoints-custom
scheme. If a curve type other than ANSI is selected remember to enable switch 8 of the option dip switches. Using the 3-
phase test set adjust the phase current to the desired trip level. Reset any current trips on the relay and press the test start
button to activate the timer and inject the current. The timer on the 3-phase Test Set should be setup to start when current
is injected and stop when the trip or auxiliary (if assigned) relay activates. Verify that the TIME 51 phase A, B, or C (which-
ever phase tested) LED has been activated and latched. Check the trip time with the times and curves located in Chapter 5.
The accuracy of the timing is 3% or ±20 ms at > 150% of pickup.
The more inverse the curve the more accurate the current source required to yield accurate time measurements. A
small error in injected current will create a larger error in time to trip due to the extreme slope of the curve.
NOTE
This test is done in a similar manner to that for the phases. However different settings and current levels may be desired to
test. Verify that the TIME 51 N LED has been activated and latched after a trip.
A variac can be used to vary the supply voltage applied to the relay. First cause a trip on the relay and make note of the
LED illuminated. The service relay H7 and G8 contacts should be open. Lower the voltage applied to the relay. The relay
should not power off and the service relay change state until below the specified range for the power supply used. See Sec-
tion 1.3 SPECIFICATIONS on page 1–6. After the relay powers off the service relay should change state and the LEDs turn
off. Now power up the relay. The relay should turn on and the service relay change state at or before the specified power
supply range. The trip LED should again be illuminated.
All terminals except filter ground and communications (H8, H9, H10, G9, G10) can be hi-pot tested. All remaining terminals
except safety ground (G12) should be connected together and the test performed with respect to safety ground. Make sure
to disconnect the filter ground (G11) before performing this test. Refer to Section 2.2.7 HI-POT TESTING on page 2–12 for
more information.
GE Power Management

6.1.8 INSTANTANEOUS PHASE OVERCURRENT TIMING TEST

6.1.9 INSTANTANEOUS GROUND FAULT OVERCURRENT TIMING TEST

6.1.10 PHASE OVERCURRENT CURVE VERIFICATION

6.1.11 GROUND FAULT OVERCURRENT CURVE VERIFICATION

735/737 Feeder Protection Relay
6.1 PROCEDURES

6.1.12 POWER LOSS/RECOVER TEST

6.1.13 HI POTENTIAL TEST

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