I noticed a lighting circuit measures only 100 volts on it. Could it be the fancy dimmer switch is sucking up 20 volts? Its a newly wired circuit from a newly installed breaker box. Other circuits measure 120V.
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Could be the dimmer. And on some digital voltmeters, could be that the voltage is OK but the dimmer is modifying the waveform enough to confuse the meter.
But make sure that the neutral is zero volts to ground, to be sure that you don't have a bad neutral connection.
Thanks .. Much appreciated.
Note that most dimmers have a "full on" setting that may take a little push to get into, especially in a new, stiff dimmer. It operates a switch that bypasses the dimming logic so that the light gets full voltage.
Half of the harm that is done in this world is due to people who want to feel important. They don't mean to do harm but the harm does not interest them. --T.S. Eliot
Thanks, but I don't think that applies to these dimmers. They have a decora style push on/off switch, with the small dimming switch to the side that uses led lights to show up where the dimmer is set at. They have some memory capability so when you turn the lights back on they return the the previsou dimmer seting.There are 3 on this circuit so I hope that the three in combination are eating up these missing 20 volts. I suppose I can easily test your theory by setting all three dimmers to full on.Thanks Again.
Three in combination? How do you do that?
Half of the harm that is done in this world is due to people who want to feel important. They don't mean to do harm but the harm does not interest them. --T.S. Eliot
Its 3 on 1 branch circuit, not in combination. Two are 3-ways that control the same set of lights. The other one controls a seperate light. But they all draw their power from the same branch. Does that make sense? I might be mixing up terminology.
Having a separate light that "draws" power from the same circuit should not cause a voltage drop unless it's drawing one heckofa lot of power. (Do you smell smoke?)The dual "3-way" dimmers will cause more voltage drop than a single dimmer (unless they're the electronic kind where one is the "master" and the other is just sending a signal). But still 20V is a bit much. I'd expect a good-quality dimmer to drop no more than about 5V when full-on, so you shouldn't see more than 10V or so between the two of them.
Half of the harm that is done in this world is due to people who want to feel important. They don't mean to do harm but the harm does not interest them. --T.S. Eliot