Installation & Operation Manual Merlin GDP2X
GDP2X - IOM Iss: 7 03-21
13
Service & Field Calibration
Overview
Detectors are pre-calibrated at the time of manufacture, therefore a field calibration is only required periodically
(usually annually) to compensate for its sensitivity and accuracy that can be inhibited by external factors. Dust,
humidity, temperature fluctuations, cleaning products, contaminants or sensor drift (ageing) can cause a decline in
sensitivity, accuracy and eventual failure. Servicing and field calibration is important to prolong the operational life and
ensure the detector is able to detect a concentration of gas as accurately and as early as possible to optimise
protection. Typical accuracy of a detector is ± 10-20% of the standard field gas concentration.
Service and field calibration should coincide with the annual service message prompted on the detection system after
each year of service/operation. The annual timer for service will begin after 5 hours of continuous power irrespective
of whether the system is used intermittently. Depending on the application and environmental factors, field calibration
can be conducted at a higher frequency determined by the end user following an appropriate risk assessment but
must be executed by a competent person.
Contact your S&S Northern representative for details of suitable field calibration kits and gases to ensure any
equipment and flow rates meet S&S Northern technical requirements.
Annual Service Message
A service screen will intermittently flash every 30 seconds after one year of detector operation. The
detector will signal the control panel. The annual message reminder will begin after five (5) hours of
continuous power irrespective of whether the system is then powered intermittently. The detector will
still operate as intended during this time.
Service Mode
Access service mode by pressing the S&S Northern logo on the main screen only. The screen will display a service
prompt. Press Yes. (Note: All alarm signals/outputs will be inhibited for fifteen (15) minutes. Proceed to service and
re-calibrate detectors if required. Upon completion – exit service mode by pressing the ‘Exit’ button on screen. If you
need more time, exit and re-enable service mode. The system returns to a normal state after fifteen (15) minutes
automatically if the ‘exit’ button is not pressed.
When service mode is enabled, the control panel will ignore all alarm signals/outputs and the gas valve will
remain active!
The panel will return to a normal operational state after fifteen minutes automatically unless service mode is
disabled manually by pressing the [EXIT] button on screen!
