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3.5
Power Failure Alarm
A power failure relay is provided to disconnect the automatic control from the battery and, therefore, limit the
drain on the battery. One (1) set of normally open and closed contacts from this relay is connected to terminals
for connection to a remote power failure alarm; refer to Figure 6. The charger will automatically resume charging
upon return of AC power.
3.5.1 Remote Alarm Connection Procedure
Before making any connections to the A12B, ensure that the AC power is off at the main breaker box and that
both of the charger’s fuses/breakers are disconnected/off. Verify that no voltage is present by using a voltmeter
at all input and output terminals. If it is desired that the annunciator be active until the Power Failure alarm
triggers, connect the annunciator/power leads to the
NO
and
C
contacts of the Power Failure alarm contacts. If
it is desired that the annunciator be inactivate until the AC Power Failure alarm triggers, connect the
annunciator/power leads to the
NC
and
C
contacts of the Power Failure alarm contacts..
EXAMPLE:
A customer wants a green lamp to be
illuminated when the charger has AC power and wants
a red lamp to illuminate when the charger loses AC
power. The customer would make the connections to
the NO and C contacts between the green lamp and
power supply, and would connect the NC and C contacts
between the red lamp and power supply.
Figure 7
– Power Failure Example Connections
(Customer Provided Equipment)
Figure 6
– Power Failure Contacts
