Optek AS56 - Page 36

Faults
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optek-sensors AS56, Version 04.2010_1.2US, 15.04.2010
www.optek.com
Tab. 11 Possible faults and remedies
Possible fault Possible remarks Cause Remedy
Failure of lamp module
• "Lamp failure" LED of
converter flashes.
• Signal loss
Lamp cable between sensor
and converter defective
• Continuity test of sensor
cable
• Exchange sensor cable for
new one.
Lamp module defective • Exchange lamp module.
Detector failure -
Detector cable between sensor
and converter defective
• Continuity test of sensor
cable
• Exchange sensor cable for
new one.
Detector defective • Exchange sensor.
Condensate formation
Unrealistic, random measuring
results
Humidity gets into optical
housing and forms
condensation deposits on
windows.
• Use airpurge, chapter 5.3,
page 22
O-Ring missing or defective
• Disassemble sensor and
check O-Rings, exchange if
necessary.
Wrong results
• Results are fluctuating.
• Zero point is drifting.
• Windows are dirty.
• Windows are corroded.
• Lamp module near failure,
lamp module near the end of
its life.
• Clean sensor window.
• Exchange lamp module.
Connection error
• No function
• No "Lamp failure" LED
message
Sensor cable from sensor to
converter defective
• Continuity test of sensor
cable
• Exchange sensor cable for
new one.
Sensor cable incorrectly
connected to converter
• Check and revise
connections.
Measuring range
exceeded
Converter indicates flashing
↑ - ↑ - ↑
Process conditions
• Amplify measuring range.
• If the measuring range cannot
be amplified, reduce optical
path length.
Wavelength-dependent
detector module reduces the
dynamic measuring range,
optical filters reduce wanted
signal.
• Use other sensor with shorter
optical path length and / or
measuring wavelength.
• Exchange lamp module.
mA-signal (output)
The mA-output provides correct
current values when measuring
results are low and too low
current values when measuring
results are high.
Connected load > 600 ohms
• Check resistance of wiring.
• Use appropriate mA-input.
Small deviations given in %
Poor calibration of the receiving
mA-input
• Compensation by adjusting
calibration of the sending mA-
output.
mA-signal (input) Small deviations given in %
Poor calibration of the sending
mA-output
• Compensation by adjusting
calibration of the receiving
mA-input.
Defect of converter
None of the above mentioned
errors can be detected.
-
• Send system (converter and
sensor) to optek for checking
purposes.