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In article .com,
says...

Keith Williams wrote:
In article .com,
says...
Don Young wrote:
Troubleshooting with a digital voltmeter is also not a good idea; a
test lamp is much better.

Why isn't a multimeter a good idea? He's measuring volts, not current,
so it won't blow the meter.

Digital multimeters have a very high input impedance and can read
high values on open circuits because of the capacitive coupling
between wires. A test lamp is a low impedance device so any
capacitive coupling becomes insignificant. If you really need to
know what the voltage is, use both (load the circuit and read with
the meter).

A test lamp is a good idea. He could also pick up one of those outlet
testers for a few dollars.

A "three-light tester" should be in everyone's toolbox. Another
tool I've found to be quite valuable is a non-contact voltage
probe.

--
Keith
I love my non contact tester, I think it's a GC. I have noticed one
thing and that is you can get a false positive if you're holding the
tester and near or standing on an extension cord. I guess it
capacitively couples to the voltage source. Still better than a false
negative :).

Indeed. I'm pretty careful even with the NC tester. A false-
negative could ruin one's day.

--
Keith