Do I calibrate the probe or the thermometer?

So, my probes are detachable from the thermometer base units. At purchase I alway get a base thermometer with matching probe and a UKAS 5 point calibration certificate. But when they are due for annual external calibration, what do I calibrate? The probe or the thermometer? It's always the base unit that is labelled and gets the unique reference number, but surely the probe attachment is equally as important? Seems a bit crazy to have to calibrate both parts, I'd probably be better just buying new each year for what it would cost me in calibration!

So, my probes are detachable from the thermometer base units. At purchase I alway get a base thermometer with matching probe and a UKAS 5 point calibration certificate. But when they are due for annual external calibration, what do I calibrate? The probe or the thermometer? It's always the base unit that is labelled and gets the unique reference number, but surely the probe attachment is equally as important? Seems a bit crazy to have to calibrate both parts, I'd probably be better just buying new each year for what it would cost me in calibration!

Dear elaine,

Maybe it depends on what you are doing with yr thermometer (thermocouple?) but it's usually economic to purchase one master unit, pay to keep it calibrated at the points you need and self-calibrate all the other units against the master. This is a perfectly acceptable procedure although it can be a bit operationally tricky if you are including temperatures like -18degC or +180degC.

Rgds / Charles.C

Oh dear, blonde moment, of course that is indeed what I'm doing! Problem solved!

Dear elaine,

Maybe it depends on what you are doing with yr thermometer (thermocouple?) but it's usually economic to purchase one master unit, pay to keep it calibrated at the points you need and self-calibrate all the other units against the master. This is a perfectly acceptable procedure although it can be a bit operationally tricky if you are including temperatures like -18degC or +180degC.

Rgds / Charles.C

Hi Charles

I assume that you mean that the probe and thermometer are the one 'master unit'?

Regards,

Tony

Hi Charles

I assume that you mean that the probe and thermometer are the one 'master unit'?

Regards,

Tony

Hi Tony,

Yes. Good point.
IMEX, at time of calibration, a matched/dated “calibration sticker” is attached to each component.

Rgds / Charles

Hi guys,

 

I use digital  probe thermometers to measure temperatures of dry feeds ( temp ranging between 30 - 95 degrees celcius).

These thermometers are calibrated once a year. My auditor advised me to do a regular in - house verification using ice and boiling water. Does someone have a procedure to do this? How should I carry out this verification.

 

Thanking you in advance,

Rudra

 

Hi guys,
 
I use digital  probe thermometers to measure temperatures of dry feeds ( temp ranging between 30 - 95 degrees celcius).
These thermometers are calibrated once a year. My auditor advised me to do a regular in - house verification using ice and boiling water. Does someone have a procedure to do this? How should I carry out this verification.
 
Thanking you in advance,
Rudra

Here you are, hope this is what your looking for and helps you out.

Here is the other attachment. For some reason i couldnt get both of them to post at the same time.

Hi,

 

There has been a lot of confusion since long between calibration and verification of equipment used to monitor CCPs , for instance, probe thermometer. I have still not yet understood the major difference between calibration and verification...

Hi,

 

There has been a lot of confusion since long between calibration and verification of equipment used to monitor CCPs , for instance, probe thermometer. I have still not yet understood the major difference between calibration and verification...

Dear Rudra,

 

(Thread getting a bit  )

 

Yes it is (and probably always will be) confusing. Should also not forget Validation.

 

NIST viewpoint on verification –

 NIST verification.pdf   4.57MB   118 downloads

These other explanations may also be helpful –

 

http://www.instron.u...oogle.co.th/url

http://www.instron.u...rification.aspx

http://www.instron.u...alibration.aspx

 

http://www.ifsqn.com...n-of-equipment/

 

Just to illustrate that you are not the only one, here is a really Geeky solution. Understandable approx. up to end of Pg3 for me.

http://www.stanford....ESS-Trucano.pdf

 

Rgds / Charles.C

of course its different words with different meanings- calibration and verification