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Without buying an expensive calibration tool, how can I accurately calibrate my multimeters?

csadam
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    Why do you need to calibrate? If you need to calibrate in order to prove to someone else that your meter is up to snuff, you might want to contact a calibration service - they have all that expensive equipment, so you don't have to. – Michael Kohne Oct 23 '10 at 17:40
  • I'm only a hobbyist with low budget. The goal of the calibration is that my 3 different multimeters do not show three very different values for the same measured object :) I've already made same lenght measurement cables for them from low resistance silicone wire, next step is to calibrate them to a good reference. – csadam Oct 23 '10 at 20:06
  • How far apart do they read right now on what value resistor? – Nick T Oct 25 '10 at 03:59

2 Answers2

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You can buy a few 0.1% resistors to calculate resistance ranges cheaply.

Voltage is tricker - if you have access to several meters you can 'calibrate by consensus', as it is improbable that they will all go out in the same direction.

Another option is buy a precision voltage reference IC - e.g. AD581 is 10V with 0.1% accuracy.

Current can also be done using voltage across a known, accurate resistance.

Amos
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mikeselectricstuff
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Bring them to your university or employer, and see if you can get them to calibrate them for you the next time they do their calibration run.

No, I'm serious. I expect that most schools and employers will be happy to see that their students and employees are developing their skills outside of the school/work environment, and when you've got a production line set up for a hundred meters already, the addition of one (or a few) more meters isn't that big of a deal.

Kevin Vermeer
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