Stray Voltage?

[doug glasscock]

I have a light switch that is fed by a 15amp breaker. The hot, neutral and ground at the light switch ceiling box are skinned back and not connected yet. With the light switch "OFF" I get 30VAC from Hot-Neutral at the ceiling box. With the light switch "ON" I get 120VAC from Hot-Neutral at the ceiling box.

Is this normal, loose connection somewhere or what??

 

[Ed MacLaren]

Re: Stray Voltage?

I'll bet you are using a digital meter. Try an analog meter and see what you get.

Ed

 

[doug glasscock]

Re: Stray Voltage?

We are using a Radio Shack Analog Multi-meter.
why would a digital read differently

[ February 24, 2003, 09:34 PM: Message edited by: doug glasscock ]

 

[hurk27]

Re: Stray Voltage?

The resone a digital meter will read a voltage when a analog wont is the analog loads the circuit down and a digital wont. but if there is a dimmer as the switch then you might be just turning it down and not pushing it off and with most paddle fan controls you will find that there is a little leakage current still going through them to the fan. but if this has a single pole switch then it must have a arc line inbetween the contacts and will bleed current try disconecting the switch if it goes away then problem solved if not there must be somthing still tied in.
also if the switch has a pilot light then this will give some bleed through current too.

 

[landelectric]

Re: Stray Voltage?

Electricians don't use meters either analog or digital for this purpose.

You are seeing a "phantom" voltage it is being induced magneticly from other cables in the area.

You need what electricians call a "wiggy". they are solenoid type voltage testers that apply a small load to the conductor under test.

You can just ignore the 30VAC indication and go on with your life, it's not real. But do make sure that the circuit is turned off while working on the circuit. Don't forget to bond the metal box to the equipment ground conductor.

 

[doug glasscock]

Re: Stray Voltage?

Just wanted to thank all of you for your responses.
Doug

 

[mikeames]

Re: Stray Voltage?

Make sure its not a solid state device or dimmer. These devices may accumulate or leake a voltage but it will dissappear under load like someone had already mentioned. I carry a good digital DMM and a wiggy just for this purpose. The wiggy will load it with a coil so you know you have some sort of power present.

 

[xrayguy]

Re: Stray Voltage?

Doug, I just want to add a little clarification. It kinda sounded like the previous poster was saying that you should not have solid state dimmers. This is not true! Solid state dimmers are very benificial. Especially if you have Halogen lighting or a DSL line.

 

[luke warmwater]

Re: Stray Voltage?

Doug, I on the other hand interpreted Mike's post to mean for you to check for these items to be the cause of your reading.