Recessed Lights

[frank_n]

I installed a bunch of 4-inch Halo H99ICT cans in a kitchen. The drywall is up, and the GC asked me to install the lamps so they will have light while they work. I installed the lamps, a temp switch, and connected the feed to the panel. When I turned on the switch, the thermal protectors flick off-on quickly then the breaker trips. These lights are on two switch legs. Individually, each switch leg does the same thing. When I took out the R20's and replaced them with a few compact fluorescents I had on the truck, everything was fine.

Before I installed these lights, I checked Halo's website and found they were capable of a 50-watt R20 with a 993W trim. However, if you look at the 993 trim page, it says to use a 30-watt R20 or a 50-watt PAR20 with a socket extender.

If the can is rated for a 50-watt lamp, why would thermal overload activate? Is it because there is no trim and the trim deflects heat?

Frank

 

[480sparky]

If the breaker trips, you've got more of a problem than the thermal cut-offs operating.

What I don't understand is your having the lights on two switch legs. Is it possible you're putting 240v into them?

 

[frank_n]

No, there is only one circuit in the Jbox. From there there are two switch legs and another wire that goes to a different switch box. The cans make a clicking noise when they flash and the breaker trips after about 20 seconds.

 

[480sparky]

Two SP switches, then? Sounds like a strange way to switch the lights.

I don't see how the thermal overloads in the cans opening could cause the breaker to trip, unless they themselves are the culprit. But I've never seen TOs operate so quickly either.

I assume since putting in CLFs, the TOs don't operate, and the breaker holds? If so, I would suspect defective TOs.

 

[frank_n]

One switch controls some of the lights, and the other switch controls the rest of the lights. All the lights are on the same circuit.

 

[480sparky]

Do ALL the TOs start opening at once, or is it just one? Do ALL the lights on one switch go on and off together, or do they act more like a scoreboard or disco, each one flashing independently?

Does the breaker trip when both switches are on, or just one?

 

[frank_n]

All the lights go on and off at once.

 

[480sparky]

Then it's not the TOs. You've got an intermittent short or an arc going on.

 

[frank_n]

Then it's not the TOs. You've got an intermittent short or an arc going on.

Since the recessed lights are on different switches, would it be safe to say that the short is between the switch box and the breaker? Why would there be a clicking noise in the ceiling?

 

[480sparky]

If the problem doesn't occur until you turn the switch(es) on, then it's after the switch(es).

First, do you have one temp switch or two?

If one, connect each switch leg one at a time to the switch and determine which switch leg contains the problem. If two, then it's easy to determine which bank of lights has the problem.

If you can remember how that bank of lights was daisy-chained together, start by opening a light in the middle of the run and disconnecting that light and all the downstream lights in the j-box.

If the problem persists, work your way toward the switch. If it disappears, work away from the switch.

Divide and conquer. Don't go light to light. Take the remaining portion of the circuit known to have the problem and begin in the middle of that section.

If you've got 10 lights on a switch leg, you'll locate the problem in 3 lights or less.

 

[Dennis Alwon]

If they operate fine with the compact fluorescent then I don't think there is a short in the fixtures. You probably have a bad incandescent bulb that is shorting the works.

 

[frank_n]

Dennis, I hope you are correct. I am going over there tomorrow night. I am going to put two temp switches in, then add the lamps one at a time. I sure hope it is a incandescent light bulb.

 

[mdshunk]

Here's a dirty trick. Put one of those flasher buttons in a fusebox under the fuse. Assign a know-it-all helper to troubleshoot the "problem". :grin:

 

[iwire]

I have not seen one of those for years, hours of fun driving Mom crazy putting them in the lamps around the house.

 

[mdshunk]

I have not seen one of those for years, hours of fun driving Mom crazy putting them in the lamps around the house.

They sell them at the small hardware stores, I notice. They were an Eagle Electric product. I think Eagle is part of Cooper now. We actually used hundreds of those flasher buttons at a factory I used to work at. They would flash a light to alert a fork truck operator that parts needed taken away or brought to a workcenter. Cheap way to flash a light when compared with the more typical SSAC brand flasher that others might normally utilize.

 

[ItsHot]

Bob and Marc

Bob and Marc

Some guys in the trade are troubleshooters! From the above post I think Bob and Marc once were "troublemakers!:roll:

 

[iaov]

Some guys in the trade are troubleshooters! From the above post I think Bob and Marc once were "troublemakers!:roll:

I think the more accurate word would be "still".

 

[Powercon]

sweet trick i will surely use this! thanks

 

[frank_n]

I went back to the job ready to troubleshoot, but when I re-installed the lamps, everything worked fine. It's been 2 days so far and everything is fine. Go figure.

 

[480sparky]

I'd call it an intermittent problem

Wait a couple days. It may very well return. :roll: