Magnum
28
1812.900A
3.6.7 High instantaneous trip option
The high instantaneous trip option is installed in 800 to
3200 ampere Magnum circuit breakers with a 100 kA
interrupting capacity. In general, the high instantaneous
trip is comprised of three small air core sensors, one in
each phase, which produce a signal and transmit it back
to the trip unit when the 85 kA withstand rating of the
circuit breaker is exceeded. The result is an instantaneous
trip by the circuit breaker. This high instantaneous trip
option permits the 800-3200 ampere Magnum circuit
breakers to be applied where a 100 kA fault is possible,
while selectivity up to 85 kA is maintained.
3.6.8 Voltage taps
On circuit breakers with Digitrip 1150 trip units potential
taps are required to monitor the three phase voltages.
Voltage taps may be placed on either the line (top) or load
(bottom) terminals of the breaker at the factory.
Figure 3-20 illustrates line-side voltage taps.
Figure 3-20: Line-Side Voltage Tap for 1150 Trip Unit
Labels Legend
OTS Overcurrent Trip Switch
UVR Undervoltage Release
ATR Automatic Trip Relay (520M and 1150 Trip Units Only)
INCOM PowerNet Communications Network
ABUS (Future Use)
A/S Auxiliary Contacts
NEUTRAL Neutral Sensor Input
GFSGND Source Ground Input
ZONE Zone Interlocking
ST Shunt Trip
SR Spring Release
MOTOR Charging Motor
LCS Latch Check Switch
Figure 3-21: Top View Secondary Connectors
1. Secondary Connector Labels
3.7 Secondary contacts and connection
diagrams
A maximum of sixty secondary wiring connection points
are available on the standard frame circuit breaker (48 on
narrow frame), each dedicated to a specific function.
The wiring points are finger safe with no more than two
wires per terminal.
Up to two secondary contact plug-in connectors (AMP),
each with 30 secondary points, are mounted on the top
rear portion of the circuit breaker. The plug-in
connectors are protected by a molded hood
(Figure 3-22).
Figure 3-22: Secondary Connector Protective Hood
1. Protective hood
1
1
To Next Page
Loading...
