Spectrex Quasar 900 Open-Path Gas Detection System - Manual (Page 26)

SafEye TM Quasar 900 Gas Detector
14 Operational Modes
3.1.3 Fault Mode
In the Fault status, there are three fault types:
 Fault 1 (2mA Output) – Non critical
If this occurs, it is due to blockage, very low signal or in the case of
partial obscuration or full beam block and detection is no longer
possible. The Detector’s proper operation can be restored (Auto reset)
during operation if the condition causing the problem is removed or
resolved. This mode will occur after a delay of 60 sec. from the moment
of the fault. This delay is important to eliminate momentary obscuration
due to passing through the beam.
 Fault 2 (2.5mA) - Misalignment
This occurs due to poor alignment.
 Low Voltage Fault (1mA Output)
In this case, detection is disabled due to low voltage being supplied to
the Detector. The Detector returns to proper operation only when proper
voltage level restored.
 Fault 2 (1mA Output) – Critical
In this case, the detection is disabled due to electrical / software
operational failure or central device (memory, processor) fault. Such
fault causes the Detector to cease operation. In case of fault in 0-20mA
loop, the output will be 0mA.
3.1.4 Zero Calibration Mode (1mA Output)
This mode zeros the base level from which the Detector will read gas.
It should only be performed when there are:
 No combustible gases present
 Clear path between the Flash Source and Detector
 Clear weather conditions.
Zero calibration must be done after installation, re-alignment and window
cleaning, using the handheld unit (or Host software on PC).