Service Manual

GSM-204-323
Control and alarm board (CAB)
31st Oct 01
Technical Description: Horizon macro outdoor
68P02902W02-A
CONTROLLED INTRODUCTION
Tech. 4–21
TMS fail alarm
A TMS fail alarm is generated by the TMS control board when any fan or heater
fails. The alarm signal is routed to the CAB through the alarms interface panel. It
is then processed by the CAB and sent to the digital alarm module.
A separate fan fail signal, generated by the TMS control board, is fed to the
digital alarm module without processing by the CAB.
Smoke alarms
Smoke alarms originate at optional (customer supplied and fitted) smoke
detectors. The alarm is then processed by the CAB and sent to the digital alarm
module. Dip switches mounted on the CAB printed circuit board are used to
inhibit the alarm signals when smoke detectors are not fitted.
Door open alarms
The BTS cabinet door open alarm is generated by the CAB when the
microswitch mounted in the top left corner of the power supply enclosure is
open-circuit.
The auxiliary equipment housing door open alarm signal originates at a door
mounted microswitch, and is generated by the CAB when the microswitch
mounted in the auxiliary equipment housing is open-circuit.