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HeyBub[_3_]

wrote:
On Wed, 16 May 2012 08:08:54 -0600, bud--
wrote:

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.

Except the OP had a CFL in the socket when they tested the voltage
across the switch.

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).

Because the meter was, as I said, misconnected for the rquired test.

Again I ask, in a slightly different form, what, in your expert opinion, is
the proper way to connect two probes to two wires?