Sigma AM-255 Computer Monitor User Manual


 
4. THEORY OF OPERATION page 13
Model AM-255
4.2. COMPONENTS
4.2.1. AM-255 Board:
The AM-255 Board is the controller board for the system. It receives information from the
system, and enables the appropriate lamps, relays, and the Sonalert. All functions of the
AM-255 board are controlled by a Programmable Logic Device.
There is also a battery monitoring circuit on the board. If the battery voltage drops below 10.5
Vdc the load disconnect will turn off the system power. When the battery voltage rises to 12.5
Vdc the load disconnect will automatically reconnect the power to the system.
4.2.2. Battery Module:
The battery module consists of a 7A/h, 12 volt sealed lead-acid battery.
4.2.3. Battery Charger:
The battery charger is a universal input, constant voltage output type designed to maintain a full
charge on the battery.