Kohler 33-125EFOZCJ, Installation Manual

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TP-6862 6/14 67 Section 9 Paralleling Generator Sets
9.5 Troubleshooting When Breaker Does Close to Bus
9.5.1 Faults Shown
Step Potential Cause Explanation Troubleshooting
Fault: Close Attempt
Fault: Fail to Close
1 Breaker status feedback
is not valid, no bus
sensing
The breaker closes but the controller does
not see a change in status. The controller
cannot see the bus is energized as the bus
sensing is not connected correctly on any
generators on the network.
Verify the wiring on the circuit breaker to
ensure that it is connected correctly. Verify
bus wiring for all nodes. Verify the
generator output is connected to the line
side of the generator breaker.
Fault: CB Status
1 Breaker status feedback
is not connected
The breaker closes but the controller does
not see a change in status. The controller
sees the bus is now live.
Verify the wiring on the circuit breaker to
ensure that it is connected correctly.
2 Breaker status is short
circuited
The controller sees the breaker is closed
even when it is not trying to open it.
Verify connection of the breaker status
wiring at the circuit breaker.
3 Breaker status feedback
is connected to the
wrong contacts
The controller sees open status for the
breaker after telling it to close, closed
status after telling it to open.
The controller is expecting the breaker
status to be an “A” contact. Verify the
circuit breaker auxiliary contacts are either:
11 and 14
21 and 24
31 and 34 or
41 and 44.
4 Breaker status feedback
is connected to a
latching contact
The breaker status indicated that it closed
when it was triggered to close but it did not
indicate that it was open when the breaker
opened. This fault will only occur if the bus
sensing is connected correctly (the
controller sees the voltage go to 0 when
the breaker is triggered to open).
Verify the breaker status input to the
controller is connected directly to an
auxiliary contact on the circuit breaker.
Fault: Bus Phase Rotation Mismatch
1 All of the bus sensing
wires are incorrectly
connected
The bus sensing wires must be connected
to phase A, phase B, and phase C of the
bus. If any two connections are reversed,
the controller can detect the reversed
connections. This fault will only occur if all
three wires are incorrectly connected.
Verify the bus metering connections.
2 The phase connections
on the paralleling
breaker are inconsistent
with the generator
The power leads from the generator to the
paralleling circuit breaker must be
connected consistently. Phase A from the
generator must go to phase A of the line
side of the paralleling (motor operated)
breaker, phase B from the generator to
phase B of the breaker and phase C of the
generator to phase C of the breaker.
Verify the output cable connections.
3 Generator sensing is
connected incorrectly
The controller measurement leads are not
connected to the appropriate output phases
or the phases are incorrectly labeled.
Verify the sensing leads from the controller
are connected to the appropriate output
leads from the generator. L1 should
connect to phase A, L2 to phase B, L3 to
phase C, L0 to neutral.
4 Breaker to bus wiring is
inconsistent
In applications where the bus sensing is
taken from a location other than the load
side of the paralleling breaker, it is possible
to connect the wiring incorrectly between
the load side of the output breaker and the
paralleling bus.
Verify the cable connections from the
paralleling breaker to the paralleling bus.