GE LPS-O - T4: Ground Directional Trip Test; T5: Ground Directional Block Test; T6: Phase Instantaneous Overcurrent Test

6-
4
LPS-O Line Protection System GE Power Management
6.2 MEASURING UNIT TESTS 6 FUNCTIONAL TESTS (USER SETTINGS)
6
where I
BPICKUP
is set as follows:
The test current,
I
op
, is single phase and applied to I
A
. Thus, the LPS-O should pick up when I
op
is greater
than or equal to
I
BPICKUP
.
2. Connect the relay as shown in Figure 4–3: PHASE TO GROUND TEST CONNECTIONS on page 4–16.
3. Set the relay into test mode 19 (IB Detector). The LUI should display
IB DETECTOR ON
4. Set the voltages to zero.
5. Set the level of
I
op
to I
BPICKUP
+ 0.1 = [________] A rms and apply to the relay. The A1 contact should
close. Lower
I
op
to I
BPICKUP
– 0.1 = [________] A rms, at which point the A1 contact should open.
6. Reduce
I
op
to 0 A.
6.2.4 T4 – GROUND DIRECTIONAL TRIP TEST
This test has fixed settings that are not user selectable. See Section 5.1.5: T4 – GROUND DIRECTIONAL
TRIP TEST on page 5–3 for testing with factory settings.
6.2.5 T5 – GROUND DIRECTIONAL BLOCK TEST
This test has fixed settings that are not user selectable. See Section 5.1.6: T5 – GROUND DIRECTIONAL
BLOCK TEST on page 5–4 for testing with factory settings.
6.2.6 T6 – PHASE INSTANTANEOUS OVERCURRENT TEST
1. Protection settings:
OVERCURRNT
(601)
50
= YES
(602)
50_DIRCNL
= NO
(603)
50PICKUP
= [________] Amps
(605)
50G
= NO
(610)
51G
= NO
LINEPICKUP
(801)
LINEPICKUP
= NO
The
50
function is calculated with the following equation:
50
= (
I
A
– I
B
) or ( I
B
– I
C
) or ( I
C
– I
A
)
where
50
is the difference in phase-to-phase current.
The test current,
I
op
, is connected to one phase and returned through another to simulate a phase-to-
phase fault. When an AB fault is applied, the difference (
I
A
– I
B
) equals ( I
op
– (– I
op
)) = 2 I
op
. Therefore,
50
will pick up when
I
op
is greater than or equal to 0.5 x
50PICKUP
.
2. Connect the relay as shown in Figure 5–1: PHASE-TO-PHASE TEST CONNECTIONS on page 5–7 for a
phase AB, BC, or CA fault. Note that the leading phase is 180° out of phase with the line to which it is
shorted.
I
BPICKUP
I
A
, I
B
, or I
C
=