Campbell CS475, Instruction Manual

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CS475, CS476, and CS477 Radar Water Level Sensor
17
The test procedures for the sensor require the following steps:
1. Double check all wiring connections.
2. Connect the sensor to your datalogger and apply +12V power.
3. Compare the Output Stage versus the Actual Stage using the Start
Measurement command ( aM! ) followed by the Send Data command
( aD! ).
4. Send the Acknowledge Active command ( a! ). This command is used to
check the presence of the sensor on the bus. Only the address is sent back
in response.
5. Send the Identification command ( aI! ).
6. Send the Start Verification command ( aV! ) followed by the Get Data
command ( aD0! ).
7. Use the Get Unit command ( aXGU! ) to ensure the units are what you
want.
8. Use the Get Water Condition command (
aXGWC!
) to ensure that the
water condition fit the body of water you are monitoring.
9. Use the Get Power Operation Mode command ( aXGPOM! ) to ensure that
the power mode is what you want.
10. Use the False Echo Learn command ( nnn.nnn! ) if you
encounter a problem that could be caused by noise.
9.2 Cyclic Redundancy Check
The cyclic redundancy check (CRC) is used to produce and send a small, fixed-
size checksum of a larger block of data to the datalogger. This checksum
detects errors after transmission or storage. The CRC is computed and added
before any transmission or storage. The CRC is also authenticated by the
recipient, after the transmission, to confirm that no alterations occurred. CRCs
are very good at identifying errors caused by noise in transmission channels.
The aV! command followed by the aD0! command will perform a CRC and
return either a 0 (OK) or 1 (failed); see Appendix C.1.10 , Start Verification
Command
(p. C-8)
, for more information.
9.3 Diagnostics and Repair
All factory repairs and recalibrations require a returned material
authorization (RMA) and completion of the “Declaration of
Hazardous Material and Decontamination” form. Refer to the
Assistance page at the beginning of this manual for more
information.
NOTE