GE LPS-D, Instruction Manual

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LPS-D Line Protection System GE Power Management
2.2 GENERAL SETTINGS 2 CALCULATION OF SETTINGS
2
107: NUM_MON - Trip Outputs To Be Monitored
Trip circuit monitoring can be used to check the integrity of the trip circuit to which the selected trip output is
connected. It does this by sensing the voltage across the trip output as shown below. If the trip circuit is intact,
almost full DC voltage will be detected across the trip output. If the trip circuit is open for some reason, there
will be no voltage, or very little voltage, across the trip output. The monitoring circuit will detect this condition,
store an event and can be programmed to close an alarm contact if so desired.
Figure 2–1: TRIP CIRCUIT MONITOR
The trip contacts are also monitored when the LPS-D initiates a trip. If the voltage across the contacts does not
drop when the trip is initiated, it is assumed that the trip circuit is not intact and an alarm is issued. If the voltage
drop concurrently with the trip initiation, the trip circuit is considered activated and no alarm is issued.
Table 2–1: NUM_TC SETTING (SINGLE PHASE MODELS)
Number of
Breakers
NUM_BKR
Number of
Trip
Circuits
NUM_TC
Breaker No. 1 Breaker No. 2
Trip Circuit 1 Trip Circuit 2 Trip Circuit 1
Φ
A
TC1-1
Φ
B
TC1-2
Φ
C
TC1-3
Φ
A
TC2-1
Φ
B
TC2-2
Φ
C
TC2-3
Φ
A
TC1-1
Φ
B
TC1-2
Φ
C
TC1-3
1 1 T1 T2 T3 - - - - - -
1 2 T1 T2 T3 T4 T5 T6 - - -
2 1 T1 T2 T3 - - - T4 T5 T6
where: TC1, TC2 = Trip Coils; T1 to T6 = LPS-D Trip Outputs
Table 2–2: NUM_TC SETTING (THREE PHASE MODELS)
Number of
Breakers
NUM_BKR
Number of
Trip Circuits
NUM_TC
Breaker No. 1 Breaker No. 2
Trip Circuit 1
TC-1
Trip Circuit 2
TC-2
Trip Circuit 1
TC-1
Trip Circuit 2
TC-2
1 1 T1 - - -
1 2 T1 T2 - -
2 1 T1 - T2 -
2 2 T1 T2 T3 T4
where: TC1, TC2 = Trip Coils; T1 to T4 = LPS-D Trip Outputs
VOLTAGE
MONITOR
52
TC
TRIP OUTPUT
(FROM ALPS)
(+) DC
(-) DC