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5.5 MOB TESTING
5.5 MOB TESTING
1. Record the pre-test values of the Protection Settings used for this test.
2. Protection Settings:
OS BLOCKING
(1601) MOBZONE = 0 (ZONE 2)
(1603) BLOCKWHAT = 0 (BLKALL)
Z1DISTANCE
(101)
Z1PHASE = NO
(104)
Z1GROUND = NO
Z2DISTANCE
(201)
Z2PHASE = YES
(204)
Z2GROUND = NO
Z3DISTANCE
(301)
Z3PHASE = NO
(304)
Z3GRND = NO
Z4DISTANCE
(401)
Z4PHASE = NO
(405)
Z4GRND = NO
5
3. Connect the relay as shown in Figure 5–1: PHASE-TO-PHASE TEST CONNECTIONS on page 5–7 for
the appropriate phase under test.
4. Set the relay to test mode 40 (Out of Step). The LUI displays the following:
OUT OF STEP ON
5. Set the voltage inputs as follows: VA: 75 V rms ∠0°, VB: 75 V rms ∠–120°, VC: 75 V rms ∠+120°.
6. Set the fault current, I
angle is 180° out of phase with the line to which it is shorted.
∠I Degrees
–85
–25
7. Set the currents in the faulted phases to 6.3 (1.3) amps rms. Reduce the voltages of the faulted phases
and check that the A1 contact closes when the voltages are within the limits shown in the table above.
8. Reduce the current in the faulted phase to zero.
9. Repeat the test for phases BC and CA. Return settings to their pretest values when completed.
Make sure that the relay is no longer in test mode; select END TEST MODE from the test mode menu. Print
out or scroll through all of the settings. Compare them with the initial settings of the relay, and change to initial
values. If the initial settings were saved to a disk file with ALPS-Link before testing, download the file to the
relay.
5-
24
, to the phase-angle value listed in the table below. Note that the leading phase
op
Volts rms
62 to 72
62 to 72
LPS-D Line Protection System
5 FUNCTIONAL TESTS (FACTORY SETTINGS)
5.5.1 T21 – OUT-OF-STEP REACH, MOB
5.5.2 ENDING FUNCTIONAL TESTS
GE Power Management
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