Over-Temperature Alarm Relay; Combined Alarm-Status Charger Monitor - HindlePower SCR series Operating Instructions Manual

18. OVER-TEMPERATURE ALARM RELAY WITH BUZZER (EJ0439)
Purpose: The Over-Temperature Alarm provides an alarm indication whenever the battery charger
internal components become overheated for any reason. A built-in audible alarm is furnished, along with
alarm contacts at TB3 terminals 47, 48, 49. This feature is standard on battery chargers rated over 300A
output current.
Description: A normally open thermostat is mounted on one or more of the heat-sensitive components
of the charger. If an over-temperature condition occurs, the thermostat closes the circuit to the audible
alarm and the alarm relay. The audible alarm may be turned off with a switch located in side the charger
enclosure. When the internal component temperature returns to an acceptable value, the alarm relay is
automatically reset. The audible alarm defeat switch should then be returned to the normal position.
19. COMBINED ALARM-STATUS CHARGER MONITOR (EJ0837)
Purpose: The Combined Alarm-Status Monitor (CASM) provides a cost-effective method to monitor
the integrity of the battery charger and the dc bus
Description: The CASM combines the monitoring and alarm functions of the High-Low AC Voltage
Alarms, High-Low DC Voltage Alarms, Ground Detection Alarm Relays, Charger Failure Alarm, and a
Common Alarm Relay. Each alarm in the CASM operates similarly to the equivalent stand-alone option
(see previous descriptions). A panel indicator and one or two form c relay contacts are provided for each
alarm function. In addition, a front-panel push-to-test switch checks the front panel indicators. This switch
tests only the CASM indicators.
The relay contact rating is 0.5 A, 125 V AC/DC, resistive. All relays reset automatically when the
alarm condition is corrected. All alarm relays have a 15 second time delay, except Charger Failure.
You may operate the Charger Failure alarm in either of two modes: True Charger Failure, or Zero
Current alarm. In the True Charger Failure mode, the CASM will not report an alarm when the charger
output current is zero, unless the charger actually has failed (the CASM performs a periodic self-test).
In the Zero Current (sometimes called Loss of Current) alarm mode, the CASM reports an alarm
whenever the charger output current decreases to zero. You may get false alarms if your normal load is
very low, or if you have two chargers connected in parallel.
To change the Charger Failure alarm mode, set the switch SW1 on the CASM PC board to the desired
mode (see EJ0837 on page 49). To change the interval of the self test in True Charger Failure mode, move
jumper J11 to the desired position (4 minutes or 8.5 minutes).
Installation: Wire remote alarm indicators to the alarm relay contacts at TB15 on the CASM PC board.
Remove the mating plug from TB15, and wire your remote monitors to the plug according to drawing
EJ0837 (page 49). If you ordered two form C contacts, wire both TB15 plugs according to the drawing. Be
sure that your monitor or other load doesn't exceed the relay contact rating.
If you have a grounded battery, disable the Ground Detection alarm circuit by moving the jumper on J7
to pins 1 - 2, and by removing the wire from R107 to "chassis GND" (see EJ0837). Putting the jumper on
pins 2 - 3 enables the Ground Detection circuit.
You can remove the Charger Failure alarm from the Common Alarm circuit by moving the jumper on
J6 to pins 2 - 3. This reduces the incidence of false common alarms, if your system has little or no
continuous load current, and you chose the Zero Current mode. This does not affect the operation of the
Charger Failure alarm relay or panel indicator.
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