Go Back  DoItYourself.com Community Forums > Electrical, AC & DC. Electronic Equipment and Computers > Lighting, Light Fixtures, Ceiling and Exhaust Fans
Reload this Page >

Ceiling light install problems: old wiring, no ground screw/wire, new fixture te

Ceiling light install problems: old wiring, no ground screw/wire, new fixture te

Reply

  #1  
Old 03-22-13, 05:48 AM
Member
Thread Starter
Join Date: Feb 2013
Location: USA
Posts: 9
Received 0 Votes on 0 Posts
Post Ceiling light install problems: old wiring, no ground screw/wire, new fixture te

Hello! Sorry for this long post. I hope you can help me! I thought installing an overhead light looked fairly simple. I didn't anticipate these problems...
Background: The dining room had an ugly chandelier in it when we bought our 1950’s house 7 years ago. The fixture stopped working not long after, but we were almost happy to see it go (a handyman here on another matter took it down for us & capped the wires/tucked ‘em away.) The room's used as a bedroom anyway, & floor and bedside lamps have worked fine for many years.) Now, though, we’d prefer a simple overhead light in the room. Internet research made it look like an easy DIY task. But upon further inspection, my setup’s not an easy “black to black, white-white, ground-ground” kinda deal…
I have 4 main problems/issues:
1. Lots of wires in the ceiling box!
2. Old wires w/cracked insulation
3. Old wires probably not compatible with newer fixtures (not rated for 90C…)
4. No ground wire/threaded hole in metal box to add ground screw & pigtail (new fixture doesn’t require a bracket I can attach to, either.)
First, the wires in the light box: 3 black, 3 white, and 1 red. No ground wire (or ground screw, or even a threaded hole to ADD a ground screw w/pigtail.) I used a neon tester, and discovered the red & one of the blacks (from the same cable as the red) are hot. The red is affected by the switch. There is no ground wire, but when I test from the red or black wire to the metal box, I show voltage. Does this mean the box is grounded? A couple of the old wires had slightly crumbly insulation, and I had just finished adding heat shrink tubing over all 7 of them (per an article I’d read) before I discovered there was no threaded screw hole to add the green ground screw w/pigtail I’d purchased. So I did more research, and began to worry about my old wiring. I read that most new fixtures have temperature requirements for supply wires. Looked at the new one I bought—sure enough, it has the 90C requirement. I don’t know what the rating is on my wire (how do I tell?—didn’t see any writing on the wiring I covered w/shrink tubing.) Although, its age and/or condition more-than-hints it’s not the higher-rated 90C stuff. Are these requirements absolute? I read some other posts here, with answers saying you can get around this issue by using lower wattage bulbs, fluorescents, or fixtures where the light doesn’t “hug” the ceiling (projecting more heat to the wires) – like chandeliers, ironically. A better fix, like adding a junction box a few feet away with the “good stuff” wire would really test my DIY capabilities...but if I could—how? Do you cut another hole in the ceiling for the second box? I’m disabled…no way can I get up into the attic and make my way clear to the other side of the house to the location I need. On the other hand, huge fire risk means I have to find a way. I did more reading on this, and I realize I’m gonna need to start saving money for the inevitable rewire—all that old wiring is just getting older! I don’t even want to think about the wiring in all the other light boxes. I’m hoping the ceiling fans have newer wire, but a proper inspection is in order I guess...
So, back to my #1, above. I read a post w/a similar wiring situation (7 wires like mine.) I’m hoping my situation will work like that one: red to the fixture black, 3 whites to white, and just wire-nut off the blacks. That leaves the fixture ground. What do I do about that? I’m going to wait a bit before trying to wire this up, as I plan to look for a lower-rated fixture (for 60C wiring.) My web search doesn’t leave me very hopeful of finding one, however. Aaarggg! I don’t think I’ll sleep tonight—too many worries (and I thought I’d have a nice little DIY project under my belt when I woke up yesterday!)
Thanks in advance for any help or advice!
 
Sponsored Links
  #2  
Old 03-22-13, 06:13 AM
ray2047's Avatar
Member
Join Date: Mar 2006
Location: USA
Posts: 33,597
Received 13 Votes on 11 Posts
First we need to know the wiring at the switch. Is this a 3-way switch situation (does the switch say on/off)?
 
  #3  
Old 03-23-13, 01:58 AM
Member
Thread Starter
Join Date: Feb 2013
Location: USA
Posts: 9
Received 0 Votes on 0 Posts
Post Sorry about that. Here's the switch info:

Ooops! The switch is a single "on-off". There's only one switch in the room (and no extras anywhere else unaccounted for that would control that light.) I haven't pulled the switch out to look at the wiring because plaster's smeared over the edge of it, holding it in. I started to, but the plaster started to peel off into the wall when I tried. If I'm going to get in there, I'll need to find something to cut into the plaster somehow...so as not to tear out a chunk of wall. What tool would be best for that, if it's necessary to get behind that switch...?
Thanks for your help!
Denise

BTW, would a photo help? I don't have access right now (someone sleeping in that room) but I could take a photo of the box tomorrow (and switch if necessary) if that would help...
 
  #4  
Old 03-23-13, 07:11 AM
ray2047's Avatar
Member
Join Date: Mar 2006
Location: USA
Posts: 33,597
Received 13 Votes on 11 Posts
Pictures can help but we need the switch pulled out to fully show all the wiring. Try a Dremel tool with a carbide disk or a utility knife to score the plaster around the switch. You can also try tapping a wood chisel to score the plaster.
 
  #5  
Old 03-23-13, 04:51 PM
Member
Join Date: Mar 2013
Location: USA
Posts: 73
Received 0 Votes on 0 Posts
The insulation typically cracks when people over the years use 100 watt bulbs, sometimes multiples, overload the intended wattage in the fixture and it bakes it as the heat transfers throughout everything touching that fixture. For you to be able to shrink tube each wire,... Wow !!!, you're good. Not a whole lotta room.
Anyway... The ground issue. You can use a TEK screw. Throw away the threaded ground screw, insert the TEK screw ( similar length of the ground screw ) into the pre-formed loop of the bare copper on the grounding tail. You'll need a battery drill with a hex head. Pick a spot clear of wiring and drill and sink it tight to the box. You said the black and the red are hot,.. but then said the red was activated by the switch. With the switch in the off position, only the black is hot ? 120 volts between black and white ( same cable ) and between black and the box or ground. ( You must have BX armored cable. ( metal clad ). Without knowing what you had before the handy man removed the fixture , It's difficult to know exactly but my guess is that the blacks get spliced together and tucked into the box. The whites get spliced together and go to the white/ neutral on the fixture. The red ( switched wire ) goes to the black on the fixture.
 
  #6  
Old 03-23-13, 05:11 PM
ray2047's Avatar
Member
Join Date: Mar 2006
Location: USA
Posts: 33,597
Received 13 Votes on 11 Posts
SoyBomb wrote:
You can use a TEK screw
Tek screws must be 10-32 to be code compliant. Some are, some aren't. Sheet metal screws are never code compliant. Best to just use a ground clip or dill and tap a 10-32 hole.
 
  #7  
Old 03-23-13, 06:40 PM
Member
Join Date: Mar 2013
Location: USA
Posts: 73
Received 0 Votes on 0 Posts
Thanks for clarifying Ray. Yes,... 0.1900 " - # 10 TEK. These are the only size my electric supply carries. Bear in mind some of the older metal boxes used back in the day are a heavier ga. than current ones and sometimes pose a problem for use with ground clips. They can flex open beyond intended angles and lose their spring retention. Ground clips in this application or used improperly can fail to make ground. Tek screws, 0.1900" ( same diameter as a 10-32 ) are idiot proof.
 
  #8  
Old 03-24-13, 05:01 AM
Member
Thread Starter
Join Date: Feb 2013
Location: USA
Posts: 9
Received 0 Votes on 0 Posts
Lightbulb Didn't think of that for grounding...

Aha--tap a hole! I bought an inexpensive tap set a couple months ago, but haven't tried it yet. (I just pulled it out after reading your replies--unfortunately, I accidentally grabbed Metric--doh! I'll exchange it for SAE tomorrow if I can...) I've never seen a ground clip "in person," but online images make me think it wouldn't work in my box. There's no room to clip anything to the box's edge...the plaster seals all the way up to the edge of the metal--no gap (guess I could cut a slit somehow?) I'll probably tap a hole or get a 10-32 TEK screw (do I paint the head green if I go that route?)

I'll get the ground squared away, first. Then I'll use my Dremel to cut the plaster, pull out the switch wiring, and report back what I find. SoyBomb's guess makes sense; when I originally pulled the wires out of ceiling box, the 3 blacks were wire-nutted together, as were the whites. (Should have mentioned that earlier, but my OP was already soooo long!) And yes, only the black is hot when the switch is off, 120V between black & white of that cable/black & box. BTW, that means the box is grounded then, right? Also, SoyBomb mentioned I might have BX armoured cable. How do I find out/get a look? Where's a good place to see my wiring--should I check various other boxes until I find one I can see behind?

Regarding the heat-shrunk wires: I don't know that I'm "good", just determined, lol. It was a little tricky...and I couldn't find my "craft" heat gun, so I used a hair dryer (took even longer!) Considering my wiring is old w/heat damage, I guess it's best I didn't blast too much heat on the wires anyway...
Thanks again! Can't tell you how much I appreciate your help, guys!
Denise
 
  #9  
Old 03-24-13, 06:46 AM
pcboss's Avatar
Forum Topic Moderator
Join Date: Jul 2002
Location: Maryland
Posts: 14,996
Received 39 Votes on 34 Posts
Unless the wiring method contained a grounding conductor or the cable had a metallic sheath, the box cannot be grounded.

Your wiring is 60 degree C or less rated insulation. 90 degree insulation started in the mid 80s in non metallic cable. It would be labeled NM-B.

Look near your panel to see your wiring method.
 
  #10  
Old 03-24-13, 07:07 PM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
Received 1 Vote on 1 Post
the wires in the light box: 3 black, 3 white, and 1 red. No ground wire (or ground screw, or even a threaded hole to ADD a ground screw w/pigtail.) I used a neon tester, and discovered the red & one of the blacks (from the same cable as the red) are hot. The red is affected by the switch. There is no ground wire, but when I test from the red or black wire to the metal box, I show voltage. Does this mean the box is grounded?
Yes the box is grounded and you can bond your fixture to ground by drilling and tapping a 10-32 hole as already described.

In addition, It sounds almost certain that the black hot wire is supplying power to the other black wires to send the power to other locations. I would splice the three black wires together, splice the three whites plus the white for the light together, and splice the black for the light to the red in the box.
 

Last edited by ray2047; 03-24-13 at 07:32 PM. Reason: Typo
  #11  
Old 11-17-13, 07:52 PM
Member
Thread Starter
Join Date: Feb 2013
Location: USA
Posts: 9
Received 0 Votes on 0 Posts
Thanks, everyone!

It took me awhile to finally get this project finished (other stuff getting in the way.) But everyone's advice really paid off, and I was able to wire this light properly. I ended up tapping a hole in the box, and using a ground screw with pigtail. Then I wired as Nashkat1 & SoyBomb suggested: spliced the 3 black wires together, the 3 whites plus the light fixture white together, and the black for the light went with the red in the box. It works like a dream...thanks again, everyone!
 
  #12  
Old 11-17-13, 08:05 PM
ray2047's Avatar
Member
Join Date: Mar 2006
Location: USA
Posts: 33,597
Received 13 Votes on 11 Posts
Thanks for letting us know the outcome.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: