CIE-A-200 Control Panel Engineering and Commissioning Manual
58
Intermittent and Recurring Faults
Smoke Sensor Failed
– Signal High
Ensure that the correct device is being investigated by comparing its description with the
device address, and / or the serial number.
Do not remove or add devices with the loop active.
Ensure that the Optical Chamber is clean, if not then replace it with a new one. If the
problem still exists consider changing the electronics module.
Note that the Sita ASD detector has the electronics module and chamber integrated into a
single one-piece housing. This unit should be replaced as a complete assembly if either the
chamber or electronics module require changing.
The loop MUST BE STOPPED & RE-INITIALISED when changing optical chambers
and detectors.
Device Faults
If the system detects a
device fault or fire activation
during initialisation, the initialisation
will not fail at that point. All devices will be operational (as long as no other faults exist).
However, the system can only ignore a certain amount of fire or fault data until initialisation is
complete, and beyond certain limits initialisation will fail and the various fault or fire activations
will be displayed.
In either case, the event generated should be dealt with before the loop is reinitialised.
Firstly, investigate and rectify any Fire activations which are displayed. These may vary from
Manual Call Points which have not been reset, to Multipoint detectors which are
contaminated.
Secondly, investigate and rectify any fault conditions which are displayed. These may vary
from ‘Input open circuit’, to a Multipoint detector with its optical chamber loose (legacy Sita
Multipoint only) indicating signal low.
Please note: A short circuit between cores with a value of between 3k and 300 ohm can cause
corruption of the data on the loop and although no Short Circuit fault is reported the system
integrity will be compromised.
The system may then be reinitialised and commissioned as required.
