Latest Discussions : Electrical & Lighting


08:06AM | 07/21/05
Member Since: 07/20/05
3 lifetime posts
I have installed a fluorescent light in my kitchen where a ceiling fan was once connected. The wires out of the box are 1 red, 2 white and 2 black (plus ground). There is a white and black on the fluorescent fixture so I connected white to white and black to black and capped the red (and grounded the fixture). The light switch will not turn on the light. On top of that there are 4 other switches that will not work. The switch for the kitchen light has a red and black attached to it and the white wires are together with a wire nut. I checked the breaker and it wasn't popped but I tripped it and the reset it just in case. Still no power to the switches. The voltage at the breakers are 240 VAC. When I turn off half the breaker there is 120 VAC. Then when I turn that side off and turn the other side on the voltage reads around 89 VAC. The same occurs on another breaker. All of the other breakers read 120 VAC on both sides or 240 VAC together as they should. I have swapped breakers but get the same results so I'm guessing it's a problem somewhere between the panel and the house.

I'm not certain what the problem could be. I have training from the Navy in electronics and the electrical that runs the gear but it's been a while...I know that the 89 VAC means something but can't recall what it means. Any help would be GREATLY appreciated.

doug seibert

08:37AM | 07/21/05
Member Since: 08/10/02
842 lifetime posts
".....The switch for the kitchen light has a red and black attached to it......"

So the switch "loop" is a black / red combination......

RE-attach the two black wires and use the RED to feed the light........

The Black wire PROBABLY feeds all the other nearby switches also so they should work now too.....

How / what are these two problem breakers connected ?


09:32AM | 07/21/05
Member Since: 07/20/05
3 lifetime posts
Both have a black and a red coming out.


05:40PM | 07/21/05
Member Since: 04/25/05
1915 lifetime posts
You might have a couple of multiwire circuits.

A multiwire circuit uses 3 conductors, 2 hots that are connected to different legs so that there is 240 volts between them. And a neutral. So that between each hot and the neutral you have 120 volts.


You description is not clear. You never have "voltage at a point". Voltage is always a measurement between to points. It is usually implied what those points are, but not in your case.

You need to be EXPLECIT.

"The voltage at the breakers are 240 VAC."

You use pural here, but later say the other breakers are ok. So is this all of them?

And between what 2 points is the 240 measured between.

"When I turn off half the breaker there is 120 VAC."

Now can you turn of half of a breaker?

"Then when I turn that side off and turn the other side on the voltage reads around 89 VAC."

Side of what? and voltage between what 2 points?

A digital voltmeter has a very high impedence and will measure "phantom" voltage on an open circuit caused by capacitive coupling to other circuits and will give strange voltages like 89 volts.


Back the light and switch. The wiring that you descibe is not typical. Unless there is a junction box someplace else (either a proper one or an "illegal" hidden one) there are not enough wires.

Are these wires in cable (sheathed electrical cable or BX) or conduit?

List how many cables or conduits are in each box and what wires are in each cable.

Unless there is a junction box either the light or the switch will need to have one more cable that supplies the power.


03:52AM | 07/22/05
Member Since: 07/20/05
3 lifetime posts
I appreciate you trying to get the clear picture. Most of time I tend to describe things the way I "hear" them in my head.

The main thing to know is that this all worked PRIOR to putting in the fluorescent light. All of the inop switches worked until the light was installed. So that's what led me to the breaker to see if it had tripped. But before I went to the breakers I checked voltages at the switches and there was 0 VAC on all of them.

The breakers I'm referring to have a red and a black coming out of them. There are two switches on each breaker...both 20 amp red switches. When I read the 240 VAC I read it with one voltmeter lead on the black and one on the red. When I switch one of the sides (switches) off I get 120 VAC. When I reverse the switch positions I get the 89 VAC. I used a 4th 20 amp breaker with the same type of red and black wires coming out as a "norm" reads 240 VAC together and 120 VAC on each switch separately. One other thing to state here is that I traced one of the suspect lines (the red that reads 89 VAC) by disconnecting it from the breaker and ohming it out to the light switch in the no break in the red line.

There is no conduit to any of the switch boxes. All have cable going to them. There are 2 cables coming from the kitchen light switch that controls the fluorescent light I installed.

I was looking through some past posts and read something about the possibility of having a GFI somewhere that connects the power coming into the house to the switches.

Hope this is a little bit more clear that my first post. In my head it's clear but getting out in a clear manner is a little more difficult.


06:57AM | 07/22/05
Member Since: 04/25/05
1915 lifetime posts
Your description of the breakers is not the way most are made. But it sounds like you have two one package, with two separate handles. Zinsco/Sylvania made some like that and they have the option of a bar or strap that ties the two two poles together so that they (therorically) work as one and used for 240 volts.

From your description it does appear that you have a multi-wire circuit, two hots sharing one neutral.

Now measuring between the two halves of the breaker with one side open is meaningless.

The one side reads 120 because when the 2nd breaker is open there someking of a load on other halve pulling that side to ground. It does not need to be much, even a night light or clock radio or cell phone charger.

Nowever there is nothing on other halve of the circuit so when you open the other halve of the breaker you are measuring an open circuit.

Now back to the switch. You say that you have two cables. One should be the supply and the other feed to the light.

Tell me what colors are on each one and what connects to what?

And measure the voltages at this cable, each one to the neutral (white).

There is no logical reason that the light should have been on a GFIC, but you never know what has been done in the past.


08:18AM | 07/22/05
Member Since: 03/31/05
265 lifetime posts
Do you by chance remember how the ceiling fan was wired? Did the fan you took down have a light also? Do you have power on any of the wires at the fixture? All this will help.

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