340 AO2000 CONTINUOUS GAS ANALYZERS | OI/AO2000-EN REV. B
Uras26: Troubleshooting
Temperature problem
Connecting leads of the temperature sensor or the heater discon-
nected
• Check the connecting leads and connectors.
• Check the fit of the leads in the wire end ferrules.
Defective thermal link
• Check thermal link for continuity and replace if necessary.
Unstable readings
Leaks in the gas feed paths
• Check the seal integrity (see page 268) of the analyzer module gas paths
and (if applicable) of the lines to the pneumatics module.
Vibrations
• Provide measures to reduce the vibrations. Permissible vibration levels:
for analyzer max. ±0.04 mm at 5 to 55 Hz, 0.5 g at 55 to 150 Hz; when in-
stalled in cabinet max. 0.01 ms
−2
at 0.1 to 200 Hz.
• Increase T90; increase switching threshold for non-linear filter (see page
163).
Loss of sensitivity
• Check the sensitivity variation:
Indication < 75 %: "Maintenance request" status signal appears. The de-
tector concerned will need to be changed soon.
Indication < 50 %: The "Failure" status signal appears.
Uneven emitter modulation
• Remove the emitter.
CAUTION: The emitter temperature is approx. 60 °C in the thermostat
version of the Uras26!
• Check if the chopper wheel turns smoothly.
• Check the clamp ring seating.
• The chopper wheel should not extend beyond the notch.
• Have the emitter and modulator checked by Service.