ADC PowerWorx Circuit Breaker Panel With Reset Switch - Manual (Page 13)

ADCP-80-570 • Issue 2 • March 2006
Page 7
© 2006, ADC Telecommunications, Inc.
1.12 Breaker Alarm Indicators
For each bus, the circuit breaker panel has one visual Breaker Alarm indicator (red LED)
mounted on the front of the panel. The breaker alarm indicator lights if any circuit breaker on
the corresponding bus trips off. Loss of power to either bus will cause the circuit breaker alarm
indicator for the corresponding bus to be off.
1.13 Alarm Operation
Each bus contains circuitry that operates a set of Form C alarm relay contacts when any circuit
breaker on the bus trips off or when input power to the bus is lost. The alarm contacts may be
used to open or close a loop connected to an external alarm system.
Alarm connections are provided though a screw-down barrier terminal strip located on the rear
side of the panel. During normal operation, the normally open (NO) contacts remain open and
the normally closed (NC) contacts remain closed. When a circuit breaker trips or power is lost,
the NO contacts close creating a connection from NO to common (C), and the NC contacts open
creating an open circuit between the NC and C contacts. When the Reset button is tripped, these
contacts return to a normal operational state.
The maximum current rating for each set of alarm relay contacts is 1.0 Amp.
1.14 Alarm Connections
The panel has a screw-down barrier terminal strip for the alarm relay contact connections. The
screw-down terminal strip consists of two single row terminal blocks, each with three 3-48
screw terminals. The screw terminals are mounted on 0.250 inch (6.350 mm) centers with a
maximum distance between barriers (maximum connecting terminal width) of 0.200 inch
(5.080 mm). The three terminals in each row are labeled NO, C, and NC. The terminals will
accept #16 to #30 AWG copper wire with insulation stripped back.
1.15 Reset Switch
The Reset switch, when tripped, stops the reporting of any current alarms due to circuit breakers
being in the off position. In this state, only new alarms are reported.
1.16 Circuit Breaker Designation Card and Holder
A circuit breaker designation card as shown in Figure 4 and a card holder are provided with the
circuit breaker panel. The card holder is intended to be attached either to one of the panel
mounting brackets, to a part of the rack in which the panel is installed, at a location close to the
panel, or to the underside of the panel, as desired.
Warning: Use of one bus only on a dual bus panel will result in false alarms for the unused bus.
Power is required on both buses on a dual bus panel for normal operation.