T8 - Ground Time Overcurrent 51G - GE LPS-D Instruction Manual

5.2 MEASURING UNIT TESTS
1. Record the pre-test values for Protection Settings 610, 611, 612, 614, and 615.
2. Settings:
OVERCURRNT
(610) 51G = YES
(611) 51G_DIRCNL = NO (direct ctrl off)
(612) 51GPICKUP = 1.0 (0.2) Amps
(614) 51GCURVE = V-INV
(615) 51GTIMDIAL = 5.0
3. Connect the relay as shown in Figure 5–2: GROUND REACH TIMER TEST CONNECTIONS on page 5–8.
NOTE: Start the timer when I
4. For this test remove the relay from test mode and assign TOCTRP to A1.
(2007) A1 = index 119; TOCTRP
5. Apply I at 3.0 (0.6) A rms and start the timer. Leave the current on until the A1 contact close and stop the
op
timer. The 51G should time out in 2.8 to 3.2 seconds.
6. Reduce I
to zero.
op
7. Repeat steps 3 and 4 with the values for I
5
below. Verify that the 51G times out within the specified time.
Table 5–1: TIME-OUT VALUES WHILE REPEATING T8
I
, A rms
op
3
6
10
8. Restore these Protection settings
OVERCURRNT
(610) 51G = Pretest setting
51G_DIRCNL = Pretest setting
(611)
(612) 51GPICKUP = Pretest setting
(615) 51GTIMDIAL= Pretest setting
OUTPUTS
(2007) A1 = Pretest setting
5-
6
is applied, and stop the timer when A1 closes (the relay trips).
op
op
51G time out, s
2.8 to 3.2
0.9 to 1.1
0.6 to 0.8
LPS-D Line Protection System
5 FUNCTIONAL TESTS (FACTORY SETTINGS)
5.2.8 T8 – GROUND TIME OVERCURRENT 51G
from Table 5–1: TIME-OUT VALUES WHILE REPEATING T8
GE Power Management