Question for all you electricians.

[Boomyal]

This should be simple but apparently I'm missing something.<br /><br />Father-in-law has a 3 recessed light cannister group above the kitchen sink. All controlled by a single switch. There are no other devices on this switched group.<br /><br />Two lights quit at one time so I went to replace the bulbs for him. One worked the other did not. I tested for juice at the socket and there was none. I assumed that the thermal doo-dad had gone out as it had in one of the other three cannisters a while back so I cut it out and wire nutted the wires. Still no light.<br /><br />I then pulled out the guts of the cannister so I could access the fixture's junction box, luckily the cover of the box faced the opening in the ceiling because there is no access from above. I determined that this light was either the 1st or most likely 2nd light in the group because it had two romex 3 wire cables entering the junction box. I fished them out, pulled the wire nuts and checked for juice. Zip, zero, nada!<br /><br />What am I missing? These three cannisters have to be wired in series, all powered by the one switch. If there was a break in the romex somewhere, at least one and possibly two of the other cannisters would have no power. <br /><br />I am stumped. This is not rocket science but without being able to access the whole program from above, it is hard to trace and diagnose.<br /><br />Any hints would be appreciated. The house is 16 y/o.<br /><br />

<br /><br />Edit: I finally was able to post this pic. My fishing pictures.com would not upload it. I had to use PhotoBucket

 

[gspig]

Re: Question for all you electricians.

You may have to start from scratch. Pull all 3 canisters. They should be wired in parallel. It could be possible that the 2nd lamp does have a thermal protector but it could be wired between light 2 and 3 instead of in front of light 2.

 

[Boomyal]

Re: Question for all you electricians.

Originally posted by gspig:<br /> You may have to start from scratch. Pull all 3 canisters. They should be wired in parallel. It could be possible that the 2nd lamp does have a thermal protector but it could be wired between light 2 and 3 instead of in front of light 2.

gspig, the thermal protector I refered to is on the positive lead inside the lite cannister itself. That is on the positive lead coming from the junction box to the bulb socket. I don't know of any kind of devices that would be on the romex coming from the switch and going to each cannister junction box,<br /><br />I tried to post a diagram of the way I think it is wired but the server won't upload my 75kb jpeg diagram.<br /><br />I picture a 3 wire romex cable coming up from the switch, entering the first lite junction box, then moving on to the 2nd junction box and finally terminating in the 3rd junction box. In each junction box then, the two wire pigtail from the bulb socket is wire nutted to the positive and the common from the romex. That is, in the first two lites you have 3 black, three white and the grounds nutted together and in the 3rd lite you just have 2 wires nutted together (one each romex and socket pigtail), each going to the bulb pigtail.

 

[Johnshan1]

Re: Question for all you electricians.

If you have no power in the fixture that doesnt work but the other 2 do work then that light is also feeding something else....<br /><br /><br />So you have 3 lights, 2 of which work...<br /><br />Check the other 2 lights and make sure all connections are good in them, if you havnt already.<br /><br />The third light that isnt working is being fed off the other lights thats obvious where you have no power at all in that light and the others still work. The fact that theres 2 wires in there indicates that its feeding something else, a light, or a recep?

 

[Boomyal]

Re: Question for all you electricians.

Johnshan, you pretty much state the obvious which is what I was hoping to avoid. To even determine which is the first and last lite on the string I have to completely disassemble the other two canisters and pull the guts down thru the ceiling to get to their respective junction boxes. Of course, along with the canister parts comes all of the blown in insulation. <br /><br />The thing that is most perplexing is that about the only way this cannister can have no juice is that it's romex connection in one of the other lite's junction box would have had to come un-wire nutted but leaving the wire connected to the socket pigtail of it's lite fixture.<br /><br />I have seen how multiple lite fixtures are wired where I have access over the uninsulated garage. The romex just goes from lite fixture to lite fixture and stops at the last one. The only difference here is that the garage lites sit on top of their junction box and do not have remote boxes like the recessed cannisters do.

 

[Johnshan1]

Re: Question for all you electricians.

I hope its an easy fix for you, I know I was kind of stating the obvious there but its all I could think of at the time Good luck, im sure others will chime in with some more input here.

 

[Boomyal]

Re: Question for all you electricians.

Originally posted by Johnshan1:<br /> I hope its an easy fix for you, I know I was kind of stating the obvious there but its all I could think of at the time Good luck, im sure others will chime in with some more input here.

Hope I didn't sound critical of your input. Did not mean it that way if I did. Thanks for your input.

 

[crab bait]

Re: Question for all you electricians.

your pretty much SCREWED.. cause it don't make sense..<br /><br />AT ALL..<br /><br />you say '3-wire'.. is it 3 insulated wires ( i.e. bk,wh,red ) an a bare ground..??<br /><br />or 2 insulated wires an a bare ground..

 

[notinbig]

Re: Question for all you electricians.

how can light two be suppling light three if there is no power at two to deliver to light three. I have a feeling (if you didn't install to begin with) is that they are wire different then you think. Wire them outside the ceiling and get them working with the wires exposed then when it all works wire it in the cieling in the correct manner.

 

[Johnshan1]

Re: Question for all you electricians.

I would say that light #2 in your diagram (the one that isnt working) is actually the end of line, and since it has 2 wires into it, its also feeding something else- maybe a switched recep or who knows, thats the only logical thing.<br /><br />-John

 

[Johnshan1]

Re: Question for all you electricians.

So in other words- the wiring goes from #1 to #3 then to #2 then to who knows where.

 

[toomanyboats]

Re: Question for all you electricians.

do this,<br />you need to figure out whats going there,get to all the wires in all the lights and the switch,find out if they switched the hot or the neutral,it should show in the switch,you need a wiggy tester,then trace each wire with a contenuety tester ,that will tell you where the wires are going and if any are broken,if its the neutral some times you can use the ground as they both go to the same buss in the panel,

 

[heyttown]

Re: Question for all you electricians.

I really dont have much info to add other then what has already been stated......Other then if these cavity spaces where the can lights are located are jammed full of insulation which you said would fall out if taken apart.<br /><br />Just make sure you reinstall those thermal overloads as they are designed to cut power off to the light if things get to hot and catch the insulation and such on fire.....

 

[Boomyal]

Re: Question for all you electricians.

Originally posted by heyttown:<br /> I really dont have much info to add other then what has already been stated......Other then if these cavity spaces where the can lights are located are jammed full of insulation which you said would fall out if taken apart.<br /><br />Just make sure you reinstall those thermal overloads as they are designed to cut power off to the light if things get to hot and catch the insulation and such on fire.....

try and find one Heyttown. Those light cannisters are extremely cheap and I would consider disposable. Problem is that you'd have to rip the ceiling apart to replace them if they are installed in a vaulted ceiling with no access from above. <br /><br />They undoubtedly die with age. When I have cut them out before, I just make sure that I slide the bulb socket bracket to the full down position so the the 65 w flood is not fully recessed above the light ring reveal escutcheon.

 

[heyttown]

Re: Question for all you electricians.

They make "old work" can lights that do come with the overload built in......Its an option anyways.....They fit in the opening the existing can light sits in.

 

[heyttown]

Re: Question for all you electricians.

http://www.homedepot.com/prel80/HDUS/EN_US/diy_main/pg_diy.jsp?CNTTYPE=PROD_META&CNTKEY=misc/searchResults.jsp&N=2984+5777&cm_ven=hd_over&cm_cat=Search&cm_pla=D-Brand&cm_ite=bid101 11496-home_depot&ovmkt=RRHSQV1MO3BS17290PGL49LQS0<br /><br /><br />Hope the link works.

 

[Grant S]

Re: Question for all you electricians.

If they are wired in series the voltage of each light will be less than that of the main feed wire.<br />Is this the case? I would have thought it would be parallel wiring with each getting full voltage.and looped on to the next one.

 

[Boomyal]

Re: Question for all you electricians.

I may have mis-stated Grant. See my diagram above. That is the way I believe them to be wired. If my assumption is incorrect that may hold the key to my problem.<br /><br />To answer Crab bait as well, my assumption from examining the #2 junction box is that the first two junction boxes have one cable entering and one leaving. Each cable has white, black and bare ground. The last junction box has only the one cable entering it.<br /><br />The incoming black is nutted to the outgoing black plus the black from the lite socket. Similarly, the incoming white, the outgoing white and the lite socket white are nutted together. Then, of course the bare grounds from each cable are crimped together.<br /><br />I'm not sure what happens to the bare ground in the #3 junction box as there is no ground wire from the lite socket.<br /><br />Like I said I have only taken apart the ??#2 lite. It takes quite a while to get the canister out of the ceiling. Once you do all you can see are the wires coming into the junction box. The destination/origin of the wires are are hidden by the blown in insulation and the ceiling joists and they cannot be viewed from above.