Bosch Appliances Home Security System D9412GV2 User Manual

Page of 74
D9412GV2/D7412GV2 | Operation and Installation Guide | 5.0  Power Supply 
 
Bosch Security Systems, Inc. | 5/05 | F01U003641B 
23 
 
5.2.4 Battery 
Supervision 
When battery voltage drops to 13.8 VDC, the yellow 
Charging Status LED illuminates. When the battery 
voltage drops to 12 VDC to 11.8 VDC, the red Low 
Battery LED lights, and the keypad or keypads display 
SERVC LOW BATT
.  The 
control panel (if programmed 
for power supervision) sends a 
BATTERY LOW
 report 
in the Modem IIIa
2
 communication format. It sends a 
TROUBLE ZN 9
 report in the BFSK format.  
If the battery is missing or shorted, the red Low Battery 
LED flashes at the same rate as the green Operation 
Monitor LED. If the control panel is programmed for 
power supervision, it sends a 
BATTERY MISSING
 
report in the Modem IIIa
2
 communication format, or 
TROUBLE ZN 9
 report in the BFSK format. 
When battery voltage returns to 13.7 VDC, the Low 
Battery LED turns off and the keypad or keypads clear 
the 
SERVC LOW BATT
 
message. If the control panel is 
programmed for power supervision, it sends a 
BATTERY RESTORAL
 report in the Modem IIIa
2
 
communication format or a 
RESTORAL ZN 9
 report in 
the BFSK format. At 13.9 VDC, the yellow Charging 
Status LED stops lighting.  
Figure 6: 
Charging and Battery LEDs 
LEDs Off When Normal
Charging Status
Low Battery
YEL
RED
 
Investigate Low Battery reports immediately: If 
primary (AC) power is off and the discharge continues, 
the control panel becomes inoperative when the 
battery voltage drops below 10.2 VDC.  
5.2.5 
Battery Charging Circuit 
Float Charge 
The float voltage for the battery charging circuit is  
13.9 VDC at a maximum current of 1.4 A, less any 
devices connected to the control panel. If the float 
voltage drops below 13.8 VDC due to overload or 
battery discharge, the yellow Charging Status LED 
lights. 
Loss of AC 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 10.0 V during an AC power loss, a load shed 
relay isolates the battery from the control panel and 
disables the control panel. Load shed protects the 
battery from being damaged by deep discharge. When 
AC power restores, the load shed relay reconnects the 
charging circuit on the control panel to the battery and 
the battery begins to recharge. 
Overcharge Load Shed With AC Present: If more 
than 1.4 A of auxiliary current draw from the control 
panel occurs, the battery supplies the current and 
begins to discharge. If this situation is not corrected, the 
battery continues to discharge and at 11.8 VDC to  
12.0 VDC, the keypads display 
Serv Low Batt
.  
When the battery voltage drops below 10.0 VDC, the 
control panel shuts down. Remove all loads to the 
control panel and disconnect AC power. Add a new 
battery and reconnect AC power. 
Reset the control panel by momentarily placing the 
reset pin in the disable position. Refer to Figure 4 on 
page 17. The red Low Battery LED continues flashing 
until the control panel resets. 
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 might cause the 
control panel to operate in an unsafe way. This 
condition generates 
WATCHDOG RESET
 reports. 
5.2.6 
Battery Discharge and Recharge Schedule 
Table 7: 
Battery Discharge and Recharge 
Schedule 
 
Discharge Cycle 
 
AC Off: 
AC Fail Report when AC fails, if 
control panel is programmed to report 
AC failure at occurrence. 
 
13.9 VDC: 
Charging float level. 
 
13.8 VDC: 
Charging status LED on. 
 
12.0 VDC: 
Low Battery and AC Fail Reports if 
programmed. Low battery LED on. 
 
10.0 VDC:
  Battery load shed (processing 
functions continue if AC is present). 
Recharge Cycle 
 
AC On: 
Load shed relay reset; battery 
charging begins; Battery Trouble and 
AC Restoral Reports sent. 
 
13.7 VDC: 
Battery Restoral Reports sent. Low 
battery LED off. 
 
13.9 VDC: 
Changing status LED off; battery float 
charged.