What is wrong with my ceiling fixture?


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Old 10-24-16, 05:35 PM
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What is wrong with my ceiling fixture?

A ceiling fixture in my kitchen
NoraLighting - 6" IC Air-Tight Line Voltage Housing
stopped working about 7 months ago.
The manufacturer sent me a replacement socket and wires, but I didn't know how to install it, so I didn't do anything.
Then it came back to life.

It worked for 6 months and then stopped.
I measured the voltage in the socket and got 30v. Didn't believe it, but it kept coming up at 30v.

What on earth could break it, fix it for 60 months, and then break it again; and produce 30v?

I am kinda guessing the heat sensor failed; doesn't make much sense because it had a LED bulb in it and they are only 110* (compared to an incandescent at 264*), but I have no other explanation.

Hopefully you do? Thanks
 
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Old 10-24-16, 06:00 PM
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You likely have a loose connection. If you take a voltage reading from the center tab of the socket to the screw shell you should get 120 volts. You say you only get 30 volts.

If you take a reading from the center tab to the can metal you should also get 120 volts. If you get 120 volts from this reading, you have a loose neutral.

Best thing to do is to remove the can by removing the 3-4 1/4" screws from inside the can and pulling the housing down from the ceiling. You can also push it up out of the way if this is easier. open the juction box and check the connections. Take a reading with your meter and see if you have 120 volts there. Hot to neutral and hot to ground. Report back what you find.
 
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Old 10-26-16, 05:53 PM
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I tested repeatedly from the center to the can and got 124v.
I tested repeatedly from the center to the threads and got about 35v.
I tested an outlet and got 121.2v, which two other voltage testers agree with.

I should mention that it goes through a dimmer switch, which is turned to full.

So this pretty much rules out the heat sensor and means it is the neutral?

The neutral could really only be bad at the socket and at the junction box. Is that right? If I get 120v at the socket connection it would then be the junction box?
Will I be able to see the junction box once I pull the can down?

But why on earth do I have 124v from center to can? Is that some distortion from the dimmer switch?
 
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Old 10-26-16, 06:15 PM
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First off you need to take the dimmer out of the equation. For testing put in a non dimmer switch.
But why on earth do I have 124v from center to can?
As Tolyn previously wrote you have a loose neutral. Does power come in at the switch or the light? If you have a single cable to the switch and black and white wires on the switch power comes in at the light. If you have two blacks on the switch and two or more whites connected to only each other in the switch box power comes in at the switch.

If power comes in at the switch redo the neutral (white wires) connection. If power comes in at the can pull the can and redo the neutral connections there.
 
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Old 10-26-16, 06:24 PM
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Power comes in at the switch. There are three fixtures controlled by the switch.
Two of them are working.

I pulled one good bulb out and tested the voltage as 121v center to threads.
I then tested the bad one; it was 121v center to can, and 30v center to threads.

I have done plenty of electrical work, but am real concerned here about the junction box being in the ceiling. Will I be able to see it clearly when I get the can down? It is not at all clear from the illustration how the connection are made.
 
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Old 10-26-16, 07:33 PM
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Will I be able to see it clearly when I get the can down?
If it is an old work can it will drop down.

Name:  4_ old work can.jpg
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If it is new work it will push up.

Name:  e16_a3.jpg
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Old 10-26-16, 07:55 PM
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Great illustration; thanks.
So the side pops off and exposes the connections. That looks doable. I thought I had to make the connection in the side and that looked impractical.

It was put in when the house was built, so presumably it is new work. Can you tell for sure from the link in my first post?
 
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Old 10-26-16, 08:05 PM
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The link shows a new work fixture.

In most fixtures the threaded shell that receives the lamp bulb is made of aluminum and has brass rivets holding it in place and making the electrical connection. In rare cases the rivets can be loose or develop corrosion between the wiring and the aluminum shell. This could be the problem in your case and that the company furnished you a new socket assembly might mean that with this particular fixture the problem is not so rare.

Once you take it apart it should be obvious how the socket is held in place. I would use the replacement socket.
 
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Old 10-26-16, 08:25 PM
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You likely have a loose connection.
Often can lights have two or three cables entering the wiring box, the less the better.
Connecting a single stranded wire to two or three solid wires requires a little more attention, the stranded wire (or a solid wire) can lose contact.

I pretwist the solids and then connect the stranded to the solid bunch.
Note I don't usually don't pretwist wires, but learned this the hard way.
 
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Old 10-27-16, 07:34 AM
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Got it fixed!

Thanks so much for your help.

It uses quick connectors. The hot and ground were solid, but one white wire was out of the connector, and a second was in poorly.

The one that was out was tinned stranded. At the base by the insulation much of the wire was missing (like it had been bent back and forth a hundred times), and the insulation was charred. I stripped a new end and put the white wires back in. The didn't want to come back out, so I figured it was good.

Should I have replaced the connector? It seemed solid and I just wanted to be done. I suppose now it is just as easy to replace it if it fails again; and it might not fail again. It could just be that they didn't put the wires in far enough the first time, and the connector is fine; right?
 
 

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