I have found some CR21X, CR10X and AM16/32 multiplexers in an old lab which have not been used for a while (they have been lying unused for several years).
Can I put them to use directly or should I send them in for calibration? I remember that dataloggers should be calibrated but not sure about MUX. do multiplexers need be calibrated too?
Alternatively, is this something I can do myself? Is there an instruction manual for calibration?
The dataloggers will operate without being calibrated. However, you can't be certain the measurements are correct if the equipment hasn't been calibrated in a long time. Campbell Scientific dataloggers are very stable long term. So, calibration is usually just verifying the readings, without needing to adjust anything on the datalogger. You would need a high accuracy voltage standard to compare the datalogger against.
The multiplexers do not need to be calibrated. The mechanical relays do eventually wear out. Repair service is no longer available for multiplexers that predate the AM16/32B.
21X are end of life. No support, repair, or calibration services are available for them.
Free support has ended for the CR10X. You can still pay to have them calibrated.