How do I Calibrate a volt meter?
I have couple cheap volt meters. They don't give show the same numbers. Any ideas how to calibrate? I'm not sure of a cheap and good way. Maybe something that plugs into 120 and then inverts to ...
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I tried various things like the 5 volt regulated voltage from a computer power supply and the 12.6 volts on a fully charged car battery 12 hours after charging and the 1.65 volts of a new Duracell AA battery.
Later I used lan inexpensive voltage reference from eBay
Ebay
I have the $8.47 one about 6th from the top and am confident it is accurate.
I have several cheap multimeters of a common type that happens to have a small voltage calibration potentiometer on its circuit board. I found that the meters are pretty stable over time periods of months but do vary tenths of a volt from a warm house to 20 below zero outside.
Since moving up to a UNI-T UT55 and a UNI T clampmeter (around $60 on eBay.ca) I haven't needed to calibrate - good thing because these meters have no calibration adjustment. I only need accuracy to the nearest tenth of a volt.
Later I used lan inexpensive voltage reference from eBay
Ebay
I have the $8.47 one about 6th from the top and am confident it is accurate.
I have several cheap multimeters of a common type that happens to have a small voltage calibration potentiometer on its circuit board. I found that the meters are pretty stable over time periods of months but do vary tenths of a volt from a warm house to 20 below zero outside.
Since moving up to a UNI-T UT55 and a UNI T clampmeter (around $60 on eBay.ca) I haven't needed to calibrate - good thing because these meters have no calibration adjustment. I only need accuracy to the nearest tenth of a volt.
