not 110 volt

One of the kitchen lights was flickering and there was noise coming from the switch when the light was flickering. I removed the cover, preparing to replace the switch.
Before doing anything, I first measured the voltage. The voltage between the bottom (hot) black wire and ground was 110 V. That's what it should be. When the switch was in the ON position, the voltage between the two black wires was 0 V. That's what it should be. When the switch was in the OFF position, the voltage between the top black wire and ground was 0 V. That's good.
However, when the switch was in the OFF position, the voltage between the two black wires was between 86 and 88 V (the reading kept changing.) This switch was in a 3 gang box. The other two switches all had 110 V between the two black wires.
About a month ago, I had another light problem in the bed room. And the voltage between the two black wires was also around 88 V.
Why isn't it 110 V?
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bet you were using a DIGITAL METER?
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My advice to you, is toss the meter and use a vol-con, wiggy, or test lamp

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Welll, for starters it should probably be 115 volts or higher. The latest standards, I believe, call for 120 V nominal, 115 - 125 V are to be expected. The much lower voltage measured across the switch shows that something is partially shorting out inside the switch, and the other readings are normal. You can get a replacement switch for as little as 39 cents at a big box, just try it. Then, with the old swich, if you can measure ohms, you may see only a few hundred ohms across the switch contacts that are supposed to be infinite ohms on open/off. But the multimeter you will probably use to measure the ohms uses only a couple of volts to measure the ohms.resistance, and if it is dirt or insects or something else breaking down inside the switch, that breakdown may not occurr until there is a much higher voltage presented to the switch, and it may look ok when you measure it. If so, you can waste time trying it out again, but I would toss it into the garbage or recycle bin.
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wrote:

Except he took that reading with the switch open, which means he's reading from hot, through the light to ground, and the switch is not in his circuit.
If this is a fluorescent light and especially if he's using a digital meter also, the reading is suspect at best.
John, the best way to test the circuit and the possible failure modes will depend on the type of light you have (incandescent, compact fluorescent, fluorescent tube). If it's a compact fluorescent, temporarily replacing the bulb with an incandescent bulb will make it easier to debug.
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John Smith wrote:

Hi, You are measuring voltage with the lamp in the socket in series. Maybe you have bad socket(arc'd, oxidized, or tarnished or plain loose contacts inside the socket). How old is your house? Any Al wiring?
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wrote:

Maybe a loose connection. Check all wire nuts in the circuit, I bet you'll find a loose wire somewhere. I'd be concerned about arcing issues and possible fire hazard.
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Phisherman wrote:

Check all grounding -
--
Zyp



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