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Bud--

On 5/16/2012 5:48 AM, HeyBub wrote:
wrote:

It is often normal to get strange readings with a digital meter, as
someone said, too much to go into here. Short answer is the wiring
is acting like a capacitor or transformer and the high impedance of
the meter is picking up voltage with a very small current. Almost
any load and the voltage will dissapear.. If the bulb was still in
the circuit, it may be a small ammount of feed through in the CFL.

Short answer is the voltmeter was not being used properly, and the
longer answer is nobody else here caught it.
Nothing to do with inacuracies of digital meters - totally a case of
not knowing how to use a meter to troubleshoot - or knowing how to
interpret the readings when the meter is mis-connected.

The readings are accurate

The readings are NOT accurate. The indicated voltage is a phantom.

Consider your assertion that the meter is "mis-connected:" The meter has two
probes. There are two wires. There are two and only two possible ways to
connect the meter and the wires. Which of the two, according to you, is the
correct way to connect all this stuff? If both of the two possibilities
yield the same result, where is the "mis-connection"?

The OP was measuring across an open switch with no load (no bulb). One
might expect zero volts. What was measured was a "phantom" voltage, as
Hey says, caused by capacitance between switched and neutral wires to
the light and the high impedance of the meter as Ralph said. It is a
rather well know quirk (inaccuracy) of digital meters.

The measurement across the switch would be meaningful with an
incandescent bulb installed. Or a low impedance meter would measure zero
volts (which would tell the OP nothing).

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bud--