Electrical troubleshooting question

[jblomenberg16]

So we have a couple light fixtures in our bathroom that seem to be burning out bulbs at a much faster rate than the rest of the house. So far I've chalked that up to those bulbs getting used the most of any room in the house, and also being some of the few incandescent bulbs in the house (that natural light seems to be preferred by my wife).

Tonight I picked up some LED bulbs in a soft white light to try those. After installing them, one light would not come on. I thought maybe it was a bad bulb, but decided to swap it with another next to it (fixture each have 2 bulbs). After swapping both worked fine. So swapped back and then the same bulb wouldn't light up again. Swapped back, and then both worked.

I know the LED's are completely different than an incandescent with a filament, and are sensitive to voltage. Anything I should be checking to see if I have an issue? Thinking about removing the fixtures and getting out the multi meter and checking the circuit.

 

[moosehead]

Assuming no wiring/fixture issues, is the circuit on a dimmer switch? A couple of years ago my wife switched some of our bulbs in the photocell lights to CFLs, and kept complaining about replacing the bulbs every few months. I "wasted" the extra money and put dimmable bulbs in. They're still running.

 

[jblomenberg16]

Assuming no wiring/fixture issues, is the circuit on a dimmer switch? A couple of years ago my wife switched some of our bulbs in the photocell lights to CFLs, and kept complaining about replacing the bulbs every few months. I "wasted" the extra money and put dimmable bulbs in. They're still running.

Good questions! No dimmer, just a standard switch. I'm assuming the wiring is correct but that is what has me wondering, since I did it (under supervision) and also passed inspection. It seems one of the fixtures was burning out lights faster than the other (both on the same switch) so wondering if the fixture itself may have something wrong in it.

 

[kjf48197]

Check all of your connections on your switches and fixture and any wire nut joints and be sure they are tight. I went to a house that had the same problem and found a loose screw on the switch. She said no problems after that.

 

[jblomenberg16]

Check all of your connections on your switches and fixture and any wire nut joints and be sure they are tight. I went to a house that had the same problem and found a loose screw on the switch. She said no problems after that.

Thanks, will check that out!

I took the cover plate off the switch box and checked voltage to the switches. 123V to one, 122V on the other. That did seem a little odd since both are fed by the same source and connected by a push in connector. I would have expected identical voltage.

 

[GodFearinGunTotin]

It'll be interesting to see what the voltage reading is. I'm wondering if you've dropped a neutral somewhere/swapped it with the other leg. I could see how a loose connection might play havoc with an LED but I'm not so sure how it would make an incandescent bulb burn out quickly.

ETA...looks like it might not be a voltage problem.

 

[GodFearinGunTotin]

Thanks, will check that out!

I took the cover plate off the switch box and checked voltage to the switches. 123V to one, 122V on the other. That did seem a little odd since both are fed by the same source and connected by a push in connector. I would have expected identical voltage.

Nah...one volt isn't something to worry about. What is the voltage at your lamp sockets?

 

[bulletsmith]

Also look for any discoloration of the screw shell of the fixture. A lose connection there can cause heat that will also cause a shorter lamp life.

 

[jblomenberg16]

Nah...one volt isn't something to worry about. What is the voltage at your lamp sockets?

All 4 lamp sockets (2 per fixture) were within .5V. Ranging from 122.2 to 122.7 Coincidentally or not ,the socket with 122.2 was the socket that wouldn't light the bulb and the 122.7 was next to it. Guessing that's not the issue at all, just coincidence.

I did notice that socket was a little harder to get a good reading. Seemed like the center post in the middle (I assume that's the supply and the threads are the ground) was a little harder to get a good contact with the probe on my multi-meter.

So maybe a slight tolerance stack up or something where the LED wasn't getting a good contact and caused it not to light up.

 

[jblomenberg16]

Also look for any discoloration of the screw shell of the fixture. A lose connection there can cause heat that will also cause a shorter lamp life.

All appeared to be nice and shiny. In this fixture all are a silver / chrome color. I did notice a difference in the center post though. So maybe there is something to it.

The only other thing I'm starting to wonder is if the lights we were using were too much for the fixture. They were 72W (100W equivalent) GE Reveals. Those in theory then of course draw a bit lower amperage. But would think that isn't the difference here, although the LED's are 60W equivalents as the previous lights were always a bit blinding in the morning.

 

[bulletsmith]

I did notice that socket was a little harder to get a good reading. Seemed like the center post in the middle (I assume that's the supply and the threads are the ground) was a little harder to get a good contact with the probe on my multi-meter.

So maybe a slight tolerance stack up or something where the LED wasn't getting a good contact and caused it not to light up.

I suspect this and the resulting heat buildup as a contributor to the short life of your lamps.

 

[Leo]

and also being some of the few incandescent bulbs in the house (that natural light seems to be preferred by my wife).

It is not your imagination that today's current incandescent bulbs do not last as long. Since the tree huggers decided incandescent bulbs were a societal problem, the manufacturing has been moved offshore. I only buy brand name, but they are now made offshore, and no longer the quality they used to be. I still have a case of USA made GE bulbs, and they last 3 or 4 times as long as the current production from china, hungary and mexico.

I cannot find the spec's right now, but I recall the operating voltage for the LED bulbs is pretty wide, like 107 to 137, as they have a voltage control board built into the base. Your measured 120 plus VAC is fine.

Without the power on, you can use needle nose pliers and slightly lift the center contact in the bulb socket to make a better connection if you think it has lost it's tension.

 

[halfmileharry]

I was taught to NEVER touch a bulb by it's base and batteries on the contacts due to oils in the skin and causing poor contact. Might be true but that's what I go with to this day.
I had to rebuild my vanity light due to cheap components and Chinese origin. The crap they use in todays fixtures is very questionable. Aluminum contacts and ultra thin wiring. IF I went over 60W before I rebuilt it I would get a lot of heat.
I now use the energy savers that are junk as well.

 

[woowoo2]

Clean the contacts of the bulb sockets.
Just because there is the correct no load voltage, does not mean that is there under load.
And....
Stay below the current / wattage ratings of the fixture.

 

[churchmouse]

I was taught to NEVER touch a bulb by it's base and batteries on the contacts due to oils in the skin and causing poor contact. Might be true but that's what I go with to this day.
I had to rebuild my vanity light due to cheap components and Chinese origin. The crap they use in todays fixtures is very questionable. Aluminum contacts and ultra thin wiring. IF I went over 60W before I rebuilt it I would get a lot of heat.
I now use the energy savers that are junk as well.

I have been changing out all the light bulbs to LED. They generate so little heat it is amazing.

 

[Bill B]

If you want regular bulbs that will last you have to buy the rough service bulbs, but they are more expensive and kick off a lot of heat.
I just had an LED bulb burn out after being installed for 4 or 5 years. I love them and detest the CFL crap.