Temperature Bath

Opps!!!, just replace the out of calibration temperature sensors with calibrated ones.

Do your calibration on the Lab.

It's safe and cheaper to buy another set of sensors other than to rebuild or reconstruct the same factory and friends/co-workers life is irreplaceable, so as yours. Consult your safety department to amend or help implement safer process procedures and standards.

Safe suggestion, however, most of our customers would have a hissy-fit about that thought. They believe you must calibrate any instrument as it is wired in place. Found out the first time I suggested removing an RTD via a plug/receptacle to allow calibration, because this one was mounted 20' above the floor on a process skid. No-way. That could change the calibration results when it was plugged back in, was their response. (I know - very unlikely) So, we wire RTD's on our skids with very long loops of wire for calibration.

I believe with a thermocouple this becomes even more important as they are affected by the temperature that gets transmitted through the wire to the terminals at the analyzer. The voltage differences along the whole wire is what you detect, not just at the junction point. So if the pathway to the analyzer from the thermocouple affects the wire temperature, that must be accounted for.

Have several spare, calibrated thermo-couples ready for installation.

R&R the old RTD and re-calibrate it in your testing lab.

Good luck

Hot work permit perhaps, or just remove the thermocouples from the hazardous area zone (you have to remove the thermocouples from the equipment to calibrate them anyway right).

Reminds me of the inquiry we got for a hazardous area rated tea kettle (no that isn't a joke). Some times you have to use common sense.

Don't be silly. Just change the installed ones for others that have been checked in the safe area.

Do you need explosion proof, or intrinsically safe?

If you don't know the difference, find someone who does.

You can only check for accuracy, you cannot "calibrate" a thermocouple or RTD.

Any adjustment calibration would be done in the indicating/controlling

instrument, which can be served with a substitute source of mV or resistance.

Calibration is not adjustment.

Intrinsically safe temperature bath? That concept is intrinsically impossible. Thank you for the laugh, though!

Use a cast iron bath tub for your temperature bath. People here have had a hard time breaking one of those.