User guide

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MRK-D-0022 V3.1 Aeroqual Series 200, 300 & 500 User Guide
Interfering gas present
Gas reactive and de-composing
before detection
Local air flow too high (ozone
sensors) or too low (VOC and
ammonia sensors)
Sensor calibration lost
Move sensor to clean air and check
reading upon exposure to known gas
concentration
Move the monitor closer to them source
of the gas
Modify the airflow into and around
sensor head.
Replace /refurbish sensor
Reading unstable
Power supply unstable
Power supply current rating
incorrect
Local air flow too high
Environmental conditions
fluctuating
EMI noise picked up via USB
cable and PC (S500 unit only)
Install stable power supply
Install power supply with correct
rating
Reduce air flow
Reduce fluctuations
Unplug cable to determine if this
reduces the instability. If this solves the
problem then isolate the power on PC
External alarm and control
doesn't work correctly (Series
300 and 500 units only)
Incorrect RJ12 pins used
No diode across external relay
coil
Diode polarity incorrect
Check pins and wire correctly
Fit diode across external relay coil
Fit diode correctly
USB communications unstable
(S500 only)
Connections broken
COM Port settings incorrect
Clock setting incorrect
Reconnect leads
Setup COM port correctly
Synchronise clock with PC. If this does
not work then the Monitor clock battery
may be flat. Return monitor to Aeroqual
for battery replacement.
8.1. Sensor Failure
The handheld monitors have inbuilt diagnostics to detect sensor faults. If the sensor fails it can be
easily replaced by simply removing and installing a new one. The failed sensor can be sent back to
Aeroqual for refurbishment or disposal. Monitor status conditions are as follows: