Man-1078_Sigma_CP_AUS_12
Page 20 of 29
This fault can only be cleared by pressing the
Watchdog Reset
button on the PCB inside the control panel.
The control panel buzzer cannot be silenced and will continue to sound until the watchdog activation is
reset.
19
Processor reset switch
Once started, the microprocessor controlling the panel should continue to run continuously without
interruption. If the microprocessor fails to run correctly it can be reset by pressing the
Processor Reset
button on the PCB inside the control panel.
This should not normally be necessary but should be done as a matter of course if the system is behaving
abnormally. The system should resume normal operation within a couple of seconds of pressing the
Processor Reset
button. Note: A
Watchdog Reset
should always be performed following a
Processor Reset
.
20
Internal indications – troubleshooting
To assist in identifying fault conditions which are not detailed on the front of the control panel, a number of
internal indicators are visible with the front cover removed as follows:
20.1
Mains fail
Indicates that the 230V AC supply is not present and the system is running on standby batteries.
If there is not a power cut, check the panels mains fuse.
20.2
Batt fail
Indicates that the standby battery has become disconnected, or that the charging circuit of the control panel
has a high resistance or has failed. Check that both batteries are connected and linked together. Test the
battery. Disconnect the battery and ensure that 28 Volts can be measured on battery charger leads.
20.3
CPU fault
Indicates that the central processor unit has failed to correctly execute code and has been re-started by the
system watchdog. The
Watchdog Reset
switch must be pressed to clear the
CPU Fault
condition.
If system does not return to normal after the
Watchdog Reset
switch is pressed then the panel is probably
damaged and the circuit board needs replacing.
20.4
Aux 24V fault
The Aux 24V and R0V terminals provide a 500 milliamp, 24V DC power supply for power fire alarm ancillary
equipment. This LED indicates that fuse protecting the R0V output has operated and the rating of this
output has been exceeded. The fuse is a self-resetting type and the supply will resume when the fault
condition is removed.
20.5
Batt low
Illuminates when the system is running on batteries and the battery voltage is lower than 21V +/-2% (the
minimum battery voltage).
20.6
Earth fault
Indicates that part of the system wiring is connected to earth. Remove all system wiring and re-connect
cables one at a time until the earth fault returns. This will indicate which cable the earth fault is present on.
20.7
Sys fuse fault
Indicates that the total power rating of the power supply has been exceeded and that the system fuse has
come into operation. Remove and review all loads and re-connect one at a time until over rated circuit trips
fuse to identify troublesome circuit.
20.8
S1 fault and S2 fault
Indicates a short or open circuit on sounder outputs. Remove wiring and refit end of line resistors. Check
sounder circuit wiring.
