Electronic – send the 0.005% 1 PPM tempco calibration resistors to find out their “true” value


edit: putting this at the top because people keep answering questions I didn't ask:

Where can I get this done cheaply by a place that is hobbyist friendly? I don't even know where to look.

I imagine there are plenty of labs that do this kind of thing, but any that I can find via google do not disclose pricing and seem geared exclusively towards volume / B2B and are not hobbyist friendly.

Are there any cheap-ish labs that are friendly to the hobbyist where I could send my precision resistors to find out their true value down to the PPM range or better? PPB would be ideal. I'm using these to calibrate my 5.5 and 6.5 digit multimeters.

Bonus question: I'm interested in getting a calibration report on my precision 5v reference and a few capacitors / inductors as well so a place that can do all of that on the cheap would be ideal.

edit: additional notes based on clarifying questions people have asked:

  1. I don't have a specific need aside from just being able to calibrate my bench multimeters up to 6.5 digits
  2. It was recommended that I send a multimeter in for calibration instead of the resistors and use it as a transfer standard. Fair enough, but whether resistors or a meter, this is the heart of the question: where can I get this done cheaply by a place that is hobbyist friendly? I don't even know where to look.

Best Answer

Calibrate the instrument

Modern DMM's use internal tables of data to implement multi-point calibration. You will not be able to do this yourself without a service manual and their test/calibration software suite.

Manual calibration with resistors will allow you create your own calibration function, but then you will have to manually apply it to each measurement (or suck the measurements through a data drain and do it there).

Factory calibration is not expensive and you don't need to be a huge enterprise to access it.

There are also 3rd party calibration services and labs. Most test equipment rental companies also have attached labs.

Here is an example of US pricing for reference. It is about 10% of original purchase price.

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