diagnose this electrical problem

[jives]

Hi all;

A while back I showed this image and said one of the bulbs would go out after about 5 minutes. Got more info. . . very strange.

Both bulbs work, are LEDs, but the problem existed with CFLs. Not the bulbs. Turn on lights, both come on.
After ~ 3-5 minutes, one DIMS, may appear to go all the way out.
Partially unscrew the lighted bulb to make it go out. The dimmed bulb now may brighten fully.
Tighten back the original bulb and it won't go on.
Unscrew both bulbs, wait a moment (don't know if that matters), screw both back in. Both work.
2-3 minutes later one bulb dims.

Rinse and repeat.
Ghosts? Gremlins? Crappy wiring?

https://www.familyhandyman.com/wp-content/uploads/2017/06/FH16SEP_LEDLIT_06-2.jpg

 

[old__man]

My guess is you have a really bad connection somewhere. Possibly a switch. That weak connection has a lot of resistance. As it heats up the connection gets worse and the resistance increases. A guess.

What kind of switch/circuit is it on? Anything else on this circuit exhibiting the same?

 

[kd3pc]

fixture, wire or switch as you have replaced the bulbs. I would drop the fixture and put up a temp one...to narrow down the problem further, break out the DMM and check voltages...

all else fails, turn off the breaker and use the DMM to ohm out things...switch included.

reliable failures are much easier to trouble shoot.

 

[jives]

My guess is you have a really bad connection somewhere. Possibly a switch. That weak connection has a lot of resistance. As it heats up the connection gets worse and the resistance increases. A guess.

What kind of switch/circuit is it on? Anything else on this circuit exhibiting the same?

My guess as well about the bad connection and heat. But where?

The light is on a dedicated 3-way switch(es) and it does not matter which switch is used. No other lights are connected to the 3-way. No other overhead lights are affected by the bulb dimming or the light being on or off.

I reckon it would be easy enough to replace the fixture. No great loss. Other thoughts?

 

[Firemike]

From what you describe, my first guess is the connections at socket where the wire connections are riveted to the inside shell of the socket, especially if it is an older fixture that had incandescent lamps in it at one time. Over the years I have seen many of those connections start heating up and slowly going bad. The CFLs take a little more amperage than LED lamps. CFL's also generate more heat. You will generally see discoloration or arcing where the small ring terminal from the wire is riveted, or where the rivet contacts the inner shell piece.

 

[BillK]

Jives,
What happens if you use regular incandescent bulbs ? The reason I ask is that I have a couple of fixtures in my house that just will not accept led bulbs. The ceramic part of the led bulbs are bigger than the glass at the base of a "regular" bulb and does not allow the bulb to go all the way into the socket and make good contact. They were driving me crazy doing stupid things until I realized what the problem was.

 

[MikeF2316]

Assuming it's that type of fixture you link to, they generally have a crimp connector where one wire from each bulb and a pigtail are connected. That's where I'd look first. Next I'd look at how those wires are connected at the bulb sockets.

 

[DC73]

Pull the fixture and check the electrical connections to the bulb sockets.

It also might be as simple as the contact at the bottom of each bulb socket just needs to be pulled up and/or cleaned to make better contact (make sure power to fixture is off).

Good luck,

DC

 

[6PTsocket]

Jives,
What happens if you use regular incandescent bulbs ? The reason I ask is that I have a couple of fixtures in my house that just will not accept led bulbs. The ceramic part of the led bulbs are bigger than the glass at the base of a "regular" bulb and does not allow the bulb to go all the way into the socket and make good contact. They were driving me crazy doing stupid things until I realized what the problem was.

Almost all sockets have a center terminal that can be bent up to deal with that. It is not an uncommon problem.

Sent from my SM-G900V using Tapatalk

 

[whisperinsam33]

Don't overthink. Change out the fixture. Then the switch. If that fails rewire, but kill the rats that are eating it first.

 

[jives]

Don't overthink. Change out the fixture. Then the switch. If that fails rewire, but kill the rats that are eating it first.

Yeah, gave the wife a reason to shop for a new light. Hopefully this will do it.