Endress+Hauser Viomax CAS51D, Operating Instructions Manual

Page: 30 / 40

Diagnostics and troubleshooting Viomax CAS51D
30 Hauser
7.2 Cyclic cleaning
Compressed air is most suitable for automatic cyclic cleaning. There is a connection for
compressed air on every sensor. The cleaning unit, which is supplied with the device or can
be retrofitted, operates effectively at a rate of 20 l/min (5.4 US gal/min).
Type of soiling Cleaning interval Cleaning duration
Severe fouling with rapid buildup 5 min 10 s
Low risk of soiling 10 min 10 s
8 Diagnostics and troubleshooting
When troubleshooting, the entire measuring point must be taken into account:
• Transmitter
• Electrical connections and cables
• Assembly
• Sensor
The possible causes of error in the following table relate primarily to the sensor.
Problem Testing Solution
No display, no sensor
reaction • Power supplied to transmitter?
• Sensor connected correctly?
• Medium flow present?
• Buildup on optical windows? 1. Connect mains voltage
2. Connect sensor correctly
3. Ensure medium is flowing
4. Clean sensor
Display value too high
or too low • Buildup on optical windows?
• Gas bubbles present?
• Sensor calibrated? 1. Cleaning
2. Eliminate gas bubbles
3. Calibration
4. Check data record and modify if necessary
5. Examine in workshop with test unit
Display value
fluctuating greatly Gas bubbles present? 1. Eliminate gas bubbles
2. Check mounting location and select a
different mounting location if necessary.
Please observe the troubleshooting instructions provided in the Operating Instructions
of the transmitter. Check the transmitter if necessary.