Service Manual

GSM-204-323
Control and alarm board (CAB)
31st Oct 01
Tech. 4–22
Technical Description: Horizon macro outdoor
CONTROLLED INTRODUCTION
68P02902W02-A
CAB additional
functions
The CAB also provides the following functions:
 Internal battery capacity test.
 Battery selector.
 Debug.
Internal battery capacity test
The CAB performs an internal battery capacity test when:
 CAB front panel BATTERY TEST push button switch is operated.
 Automated self-test carried out periodically.
 Initiated remotely from the OMC-R.
During the battery capacity test, the CAB sets the TOPSM outputs to –43 V by
adjusting the voltage trim signal so that the internal batteries supply the cabinet
loads. The CAB then monitors the time taken for the battery terminal voltage to
drop to –44 V or times out after 15 minutes. The CAB front panel battery
capacity LEDs indicate the discharge time, and a relay-generated signal is sent
to the OMC-R. The LEDs and relays remain active displaying the result of the
last test conducted.
The internal battery capacity test is remotely initiated by short circuiting the site
output relay 1 common and normally open contacts (C and NO) of PIX0. The
results of the test are reported by site alarm inputs 1 to 3 to the OMC-R.
> 5 mins PIX0 site alarm input 3 short circuit.
>10 mins PIX0 site alarm inputs 2 and 3 short circuit.
>15 mins PIX0 site alarm inputs 1, 2 and 3 short circuit.
Internal battery capacity test cannot be initiated if there are system alarms
active, the door microswitch must be pressed to override the door open alarm.
If an alarm occurs during the test, the TOPSM is reset to its normal temperature
compensated operating voltage and the battery discharge test is interrupted.
The CAB then responds to the alarm signal as normal.
The dip switches SW 4 inhibit or set periodicity (between 1 and 30 days) of
automated internal battery capacity test, (default setting is inhibited).
NOTE
PIX0 site alarms are connected to the CAB through PL2 of
the alarms interface board. PL2 is disconnected and tied
back when supplied, if this functionality is required PL2
must be connected to the alarms interface board.
The battery capacity test discharges the internal batteries
to –44 V dc. If an external power supply failure occurs
immediately after the test, the battery back up duration is
reduced to approximately 3 minutes. The internal batteries
recharge to approximately 80% capacity in less than one
hour.