Fluorescent Lighting Fixture Not Dropping Full 120V


Old 01-31-18, 08:27 AM
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Fluorescent Lighting Fixture Not Dropping Full 120V

Huge thanks to Pjmax for helping me fix my other simple issue of rewiring two switches. It worked well but now I have to figure out whats causing my actual problem.

I have a Fluorescent Lighting Fixture with the G24Q-2 base. When I plugged in a new light, it didn't come on. When I was replacing the switches controlling the fixtures I made sure to take a reading with my DMM and got a full 120V on the switch, yet when I read the voltage directly on the outlet itself I only get 8V.

What could be causing that issue? How should I diagnose the problem? Somewhat related, we did have rats for 2-3 weeks a while back before calling the exterminator. I mention it because they did chew through our AC wiring going out to the condenser and I had to run a new wire through the crawl space.
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Old 01-31-18, 09:27 AM
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When you say you measured the voltage at "the outlet" where exactly did you measure? At an outlet on the wall, the lamp socket on your light fixture...?

Have you checked the light fixture to make sure it is getting power?
Old 01-31-18, 05:57 PM
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Apologies, wording is obviously not clear. Measured 120V at the switch, which only controls a single light in the same room, and then measured the voltage in the lighting fixture socket/outlet itself and I'm only getting 8V, and obviously because of that, no light. My next step was probably going to take down the lighting fixture since it's pretty easily secured with just screws and see what's going on there.

What would be the cause of a voltage drop like that though? I don't think there are any J-Boxes between the switch and fixture, so it seems like it'd be an all or nothing situation.
Old 01-31-18, 06:09 PM
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Since you are measuring some voltage.... I'd think it was an open neutral. When you take down the fixture.... measure from white to black (or the two lamp connections) and then measure from hot to ground.
Old 01-31-18, 06:11 PM
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You are obviously trying to check the voltage after the ballast. Try checking the voltage before the ballast and you should get 120 volts.
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