User Manual

Maintenance a n d Troubleshooting 8-29
Problem
Velocity sensor data seems erratic.
Possible
Causes
Sensor m ay be di rt y.
Sensor m ay be f aul ty.
Analog board may be faulty.
Possible
Solutions
Clean the sens or.
Check t he sensor connections .
Check the vel oc i ty paramet ers.
Contact your regional ADS represent at i ve.
Replace the s ensor.
Replace the monitor if defective.
Problem
Velocity sensor readings are abnormally high.
Possible
Causes
Sensor m ay be covered with silt .
Sensor m ay be out of the fl ow.
Flow may be reversed or s l ower than 0.5 ft/s (0.15 m/s).
Possible
Solutions
Check the site c ondi tions, and rel oc ate the sensor if
necessary.
IS Pressure Depth Subsystem
The following tables contain general troubleshooting techniques for
the pressure depth subsystem.
Note: Contact your regional ADS representative for
further diagnosis before replacing a sensor.