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SE-134C Ground-Fault Ground-Check Monitor
Rev.
3
Pub. SE-134C-M, December 16, 2009.
If the SE-134C is used in a ground-fault-only
application, an SE-TA6A must be connected to the
ground-check and cable-ground terminals to validate the
ground-check circuit. See Fig. 1.
2.3 R
ESET
All ground-fault trips are latching and ground-check
trips can be latching or non-latching. To reset ground-
fault trips or latching ground-check trips, press the
RESET switch or short the RESET terminals 9 and 10.
See Fig. 1.
Cycling the supply voltage will also reset ground-fault
trips; however, if the ground-check circuit is configured
for latching fail-safe operation, the ground-check circuit
will trip when supply voltage is applied.
The single-shot reset circuit responds only to a
momentary closure; a jammed or shorted switch will not
maintain a reset signal.
2.4 T
RIP
R
ELAY
Isolated, normally open (Trip A, terminals 24 and 25)
and normally closed (Trip B, terminals 22 and 23)
contacts are provided for use in a contactor- or breaker-
control circuit. With no connection between terminals 12
and 13, the SE-134C trip relay operates in the fail-safe
mode. This mode is used with undervoltage devices
where the trip relay energizes and its normally open
contact closes if the ground-fault and ground-check
circuits are not tripped. This mode is recommended
because:
— Undervoltage devices release if supply voltage
fails.
— Undervoltage ground-check circuits do not allow
the power circuit and open cable couplers to be
energized until the ground-check loop is verified.
The fail-safe mode of operation of the SE-134C trip
relay can be used for shunt-trip circuits with a stored-
energy trip source. In this case, the normally closed trip
contact is used—the contact opens when the SE-134C is
energized and the ground-fault and ground-check circuits
are not tripped. Care must be taken to ensure safe and
correct operation during power up and power down.
Connect terminals 12 and 13 for non-fail-safe trip relay
operation with shunt-trip devices. In this mode, the
normally open trip contact is used—the trip contact is
closed when a ground-fault or ground-check trip occurs.
Shunt-trip circuits are not fail-safe and are not
recommended because:
— Shunt-trip devices do not operate if supply voltage
fails.
— Shunt-trip ground-check circuits allow the power
circuit and open cable couplers to be energized for
a short interval after supply voltage is applied.
C
AUTION:
The SE-134C is not a lock-out device. Follow
lock-out procedures for maintenance.
3. I
NDICATION
3.1 G
ROUND
F
AULT
A red LED indicates a ground-fault trip and the
remote-indication relay GF is energized when the ground-
fault circuit is not tripped (fail-safe indication-contact
operation). A green LED indicates a current sensor is
correctly connected. If the SE-CS10-series current sensor
is disconnected or shorted, the green LED will go out and
the ground-fault circuit will trip. If the sensor fault is
intermittent, the ground-fault circuit will trip and the
green LED will flash to indicate that the trip was initiated
by a sensor fault.
3.2 G
ROUND
C
HECK
A red LED indicates a ground-check trip. A green
LED indicates a valid ground-check loop and the remote-
indication relay GC is energized when the ground-check
loop is valid (fail-safe indication-contact operation). Two
yellow LED’s indicate the status of an invalid ground-
check loop. OPEN indicates the loop resistance exceeds
the trip resistance and SHORT indicates the ground-check
conductor is shorted to the ground conductor. A flashing
yellow LED indicates the corrected cause of a latched
ground-check trip.
3.3 P
OWER
The green POWER LED indicates that the internal
power supply is on.
3.4 D
IAGNOSTIC
E
RROR
The red DIAGNOSTIC ERROR LED indicates that an
internal error caused the SE-134C to trip. Return the
SE-134C to the factory if a reset does not clear the trip.
Induced ac current in the ground-check loop can cause
the LED to flicker. This is a normal condition and does
not indicate a diagnostic error; the ground-check
monitoring circuit is not affected.
4.
I
NSTALLATION
4.1 G
ENERAL
This ground-fault ground-check monitoring system
consists of an SE-134C Monitor, an SE-CS10-series
Current Sensor, and an SE-TA6A-series Termination
Assembly connected as shown in Fig. 1. Select
applications can use a combination of SE-TA12A and
SE-TA12B Termination Assemblies. See Technical Note
GC-11. If required, remote indication and reset can be
with standard pilot devices, or with an RK-132 Remote-
Indication-and-Reset Kit.