Battery Supervision (Continued)

When battery voltage returns to 13.7 VDC the Low Battery LED goes out. If the panel is programmed for power supervision, it transmits a BATTERY RESTORAL report in the Modem II transmission format or RESTORAL ZN 9 report in the BFSK format. At 13.9 VDC the Charging Status LED goes out.

Investigate low battery reports right away: If primary (AC) power is off and the discharge continues, the panel becomes inoperative when the battery voltage drops below 10.2 VDC.

Battery Charging Circuit

Float Charge

The float voltage for the battery charging circuit is 13.9 VDC at a maximum current of 1.4 Amps. Deduct any continuous load for devices connected to the panel from 1.4 Amps to find the actual current available for charging.

Load Shed Relay protects battery: During an AC power loss the battery supplies all power to the security system. If the battery voltage falls below 10.2 volts during an AC power loss, a “load shed” relay isolates the battery from the panel and disables the panel. Load shed protects the battery from being damaged by deep discharge. When AC power restores, the load shed relay resets and battery voltage is again available.

Reset or power down required for shorted battery: If the D9112 determines the battery is shorted, it uses the load shed relay to disconnect the battery. You must reset or power down the panel after correcting the problem to reset the load shed relay and reconnect the battery.

Reset the panel by momentarily placing the reset pin in the disable position. See Figure 3. The red Low Battery LED continues to flash until you reset the panel.

A shorted battery condition is created either by a shorted cell inside the battery or by a short on terminals 4 and 5. A shorted battery may generate WATCHDOG RESET reports.

Battery Discharge/Recharge Schedule (No AC Power)

Discharge Cycle

AC OFF

AC fail report when AC fails if panel is programmed to report AC failure at

 

occurrence.

13.9 VDC

Charging float level

13.8 VDC

Charging Status LED on

12.1 VDC

Low Battery & AC fail reports if programmed; Low Battery LED on

10.2 VDC

Battery load shed (processing functions continue if AC is present)

Recharge Cycle

AC ON

Load shed relay resets, battery charging begins, battery trouble and

 

AC restoral reports sent.

13.7 VDC

Battery restoral reports sent, Low Battery LED off

13.9 VDC

Charging Status LED off, battery float charged

 

D9112

Operation & Installation Manual

 

 

© 1993 Radionics

74-06144-000-C 2/96

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Bosch Appliances D9112 Battery Charging Circuit, Battery Discharge/Recharge Schedule No AC Power, Float Charge