Multimeter notes: Difference between revisions
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If you're working in industry and calibrating things, this is important. | |||
Most things hobbyists do, though? | |||
Say, when I care to check whether the Vcc line is at 5, 3.3V, or 0V, | |||
I don't care whether it's three digits or four-digit accurate. | |||
If I want to check a battery, I'm guessing what 1.2, 1.5, 3.4V, 12.1V or 13.7V mean about what's happening, | |||
then I'm not bothered unless it's more than a few percent off. | |||
AC is its own topic, because | |||
Assume that cheap multimeters are not any better than 1% on DC voltage and current. | |||
AC voltage and current is its own topic, because | |||
cheaper variants ''assume'' a sinusoidal waveform in their mains measurement, and | cheaper variants ''assume'' a sinusoidal waveform in their mains measurement, and | ||
only more expensive ones sample | only more expensive ones actually sample that any better. | ||
Also, some functions are inherently a little harder to do than others, e.g. | |||
* very high resistance. | |||
* lower capacitance | |||
* very low resistance (in that the test cables may be too thin and at some point you're measuring ''them'') | |||
Really cheap no-name multimeters may be be 2 or 3 or 4% ''in some functions''. | |||
Expensive Brand multimeters tend to be better than 1% on most functions, | |||
but even people | |||
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==Multimeter resistance figure slowly increasing== | ==Multimeter resistance figure slowly increasing== | ||
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