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Dual Zone Digital Location Control Unit Installation and Operation Manual
Interposing cable short circuit
Caution:
A short circuit on the interposing cable activates a fire condition.
Ensure that this does not contravene any applicable local standards.
Reduce the risk of a short circuit on the interposing cable by selecting a suitably
robust cable or by providing additional protection (for example, a conduit).
A short circuit on the interposing cable activates an alarm for the corresponding
zone and displays the alarm location on the LCD as <4M (<13FT), as shown
below.
ZONE 1: <4M
ZONE 2: OK
ZONE 1: <13FT
ZONE 2: OK
The detection system can only be returned to normal status by repairing the
damaged interposing cable.
Fault conditions
The control unit indicates zone faults, relay faults, interference faults, and ground
faults.
If a fault condition occurs:
• The corresponding Fault LED on the front panel illuminates
• An audible buzzer activates
• The corresponding zone fault relay activates
• The LCD displays a description of the active fault
See below for more details on each fault indication.
Zone fault
A zone fault is indicated when an open circuit exists on the wiring of the zone –
this can be an open circuit on the sensor cable itself or the interposing cable (if
used).
ZONE 1: FAULT
ZONE 2: OK
Note:
A 1 k
Ω end-of-line resistor is required at the end of the sensor cable to
monitor the integrity of the circuit. If the EOL resistor is not present (or has an
incorrect value), a zone fault is indicated.
