Wiring Question Phanton Power when switch off

I wired up some lights with a dimmer switch. When I have the switch in the off position I am still showing 67 volts. That is accross the Netural( White) and the Load (Black) Wire. If I measure between the netural and ground it is Zero and if I measure between the Load and ground I get 67 volts. Where have I gone wrong. Thanks for the help
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sdppm wrote:

A common question. You are probably measuring with a good digital meter. You are seeing a "phantom voltage". There is capacitive coupling - as between a hot wire and switched wire to and from the switch. This produces a very small current, but produces a reading on a good high resistance meter. A light bulb with pigtail leads will indicate if voltage is actually present.
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bud--

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prove it by measuring voltage between your left hand and your right hand. They can be that sensitive.
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I had disconected the string of lights and thats when I show the 67 volts. I just hooked up the lights and measured the voltgage and it was 32 volts when the lights were hooked up. Once again this is in the off position not just the dimmer being set to low. The dimmer has a rocker switch and a slider. These voltgages are coming with the rocker switch in the off position
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sdppm wrote:

IGNORE THE METER READING!
The meter is lying.
What you see is a phantom.
Working voltage does not exist.
Forget about it.
If the meter doesn't read 120 then the actual voltage is zero.
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You keep talking about the digital meters and there sensitivity. Would I be better off with the old type meter and would the reading be more true
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sdppm wrote:

I trust that's not intended to mean that he uses his hand to hand (through the chest) boody resistance to load the circuit he's measuring. That could be problematic if there really happens to be a low impedance source behind that voltage. <G>

A digital meter DOES give you a true reading of the voltage across it's input leads. AAMOF it gives you a TRUER reading of the value of the voltage source than a lower impedance meter will when the source impedance is high.
It just won't put enough of a load across what it's connected to to prevent miniscule currents flowing through capacitive coupling (or sometimes leakage resistance) from creating a significant voltage across the meter's very high input resistance. That's what's taken on the name "phantom voltage".
As suggested above, connect a light bulb (A 6 watt incandescent night lite will do fine.) in parallel with the meter's input leads and see what it reads then in your particular situation.
Jeff
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Jeffry Wisnia
(W1BSV + Brass Rat \'57 EE)
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sdppm wrote:

An analog meter would help, but what you really need is a lot cheaper.
Known good light bulb in a porcellin (sp?) or plastic socket and pigtail leads.
If the bulb glows, you have a problem. If the blb doesn't glow, no problem.
It won't glow.
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Hi,
It can depend on the dimmer. Some dimmers, like the Lutron Diva's have a small glow lamp in the switch that glows when the switch is off. They draw a small amount of power to glow. The current also goes through the light bulb, but it is so low that the bulb does not light up.
Warmest regards, Mike.
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sdppm wrote:

It's obvious you are leaking voltage through the switch.
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Blattus Slafaly ? 3 :) 7/8

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Blattus Slafaly 0/00 :) wrote:

Read the respomnse of poster "bud" in line above.
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I just want to make sure when you say off, you really mean off. On most dimmers you either slide a switch or rotate a knob to brighten or dim the lamp. And then there is a separate off, usually either a distinct click at the dim end of the rotation, or else you have to push in and click the switch to get "off". So you are really turning the dimmer off as opposed to just setting it all the way to the dim end of the range? You probably already know that but I wanted to ask just to make sure rather than ASSume. The capacitive coupling with a digital multimeter is probably the true cause.
Ken
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sdppm wrote:

You didn't say whether those "some lights" were fitted with bulbs when you made your measurements. If they were, and they are incandescent bulbs, then what you wrote is highly unlikely.
I'm betting that the bulbs aren't in place and all the previous folks who said your meter is just responding to a very weak microamp sized capacitively coupled current are correct.
If the bulbs are in place, but they are not glowing dimly or at least feeling warm to the touch after that 67 volts has been applied to them for some time, then you need a get a pro in there to figure out what kinds of electronic poltergeists have invaded your home.
HTH,
Jeff
--
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(W1BSV + Brass Rat \'57 EE)
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