Campbell Scientific CS440 Liquid Level Sensor - Manual (Page 11)

CS440 Liquid Level Sensor
7
• Check battery condition (physical and *6 mode of the datalogger)
• Check all sensor readings (*6 mode of the datalogger); adjust transducer
offsets if necessary
• Check recent data (*7 mode of the datalogger)
• Perform routine maintenance suggested by manufacturers
See datalogger manual for more information on *6 and *7
modes.
6.2 Every Three Months
• Change batteries (as needed--may be less often)
• Replace enclosure desiccants
• Check calibration of all sensors
• Inspect probe cable conditions for deterioration or damage
• Check wire connections ensuring they are still secure
6.3 Every Two to Three Years or on a Rotating Schedule
Send the transducers to the factory or laboratory for inspection and have them
serviced and/or replaced as needed.
7. Troubleshooting Hints
Problem:
Unit is not responding to logger or responding erratically.
Suggestion:
Check the electrical connections (White is +V and Blue is Signal Return) to
ensure proper connection to the logger. Some loggers require the use of an
external termination resistor. In this case, the signal return is generally
connected to an input together with one lead from the resistor (make sure both
leads are securely connected in the wiring terminal and that the wire itself, not
the insulator is secured within the wiring terminal). The other resistor lead is
typically connected to a Ground (G) or analog ground (AG) terminal on the
wiring panel. This resistor is typically of a value of 100 or 125 Ohms. Consult
CSI with further questions on this matter.
Problem:
Transducer appears to be operating properly but data shows a periodic or cyclic
fluctuation not attributable to water level changes.
NOTE