Rob writes:

I have several DMMs, including a Fluke 77. Let's say I'm testing a
high voltage, possibly charged cap such as a motor run capacitor. Is
it safe to use the DC voltage measurement function to see if the cap
has been safely discharged? What about on cheaper DMMs, is this

Yes, as long as you are on a range that exceeds the voltage rating of the
cap since there may be no way of knowing how high it is charged. Or, if
an autoranging meter, then the maximum voltage of the DMM is more than the
maximum possible voltage of the cap.

The input resistance of most DMMs is 10M ohms. They will not be effective
at discharging any but the smallest uF caps in finite time though. But to
check if a cap is charged, sure. In fact, it's a good habit to get into.

typically possible? Does it make sense to measure the resistance
across the leads of a cheap DMM with another DMM when it is in DC
Voltage mode to see if this would be the case?

Try it, though the resistance will be stated in the specifications.

Ignore the several obnoxious replies. These sorts of questions are perfectly
appropriate for this newsgroup.

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