T15 – Ground (Zone Backup) Timer Tests - GE ALPS Instruction Manual

5 FUNCTIONAL TESTS (FACTORY SETTINGS)
, to the phase-angle value listed below (increase VA, VB, VC to 75V when ∠ I
Set the fault current, I
5.
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∠I DEGREES
VOLTS RMS
–49 56 to 63
–79 62 to 72
–109 56 to 63
†
Reference only
6. Set the fault current to 2.3 (0.5) amperes rms. Reduce the faulted phase voltage and check that the A1 contact closes
when the voltage is within the limits shown above.
7. Reduce the fault current to zero. Note that the trip target indication concurs with the fault. An AG fault is displayed as
TRIP AG Z3 "DIST", where "DIST" is the displayed target.
8. Repeat the test for BG and CG faults.
1. For this test, remove the relay from test mode. Record the pre-test values for all Protection Settings used in the test.
2. Protection settings:
LINEPICKUP
(901) LINEPICKUP = NO
Z1DISTANCE
(101) Z1PHASE = NO
(104) Z1GROUND = NO
Z2DISTANCE
(201) Z2PHASE = NO
(204) Z2GROUND = YES
(209) Z2P_TIME = 1.0
(210) Z2G_TIME = 1.0
Z3DISTANCE
(301) Z3PHASE = NO
(304) Z3GRND = YES
(307) Z3P_TIME = 3.0
(308) Z3G_TIME = 3.0
Z4DISTANCE
(401) Z4PHASE = NO
(405) Z4GRND = YES
(410) Z4P_TIME = 5.0
(411) Z4G_TIME = 5.0
OUTPUTS
(2007) A1 = Z2GTMR; Index 129
a) ZONE 2 TIMER
3. Connect the relay as shown in Figure 5–2: GROUND REACH TIMER TEST CONNECTIONS on page 5–7 for the
appropriate phase under test.
4. Set the voltage inputs to the following values:
VA: 55 volts rms ∠0°,
VB: 67 volts rms ∠–120°,
VC: 67 volts rms ∠+120°.
Set the phase angle of the fault current I
5.
6. Apply the fault current at 8.2 (1.6) A rms to the relay and start the Precision Timer (the fault current should not be
ramped, but applied at the required level). This is an AG fault that is within pickup of all four zones.
GE Power Management
DISPLAYED TARGET
–
290 to 310
–
5.3.6 T15 – GROUND (ZONE BACKUP) TIMER TESTS
to –55°.
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ALPS Advanced Line Protection System
5.3 ZONE REACH AND TIMER TESTS
†
= –79°).
op
5
5-11