Black wire painted white

Reply

  #1  
Old 01-29-07, 06:14 AM
Member
Thread Starter
Join Date: Jan 2007
Posts: 9
Black wire painted white

I'm putting up some sconces operated by a 3 way switch. There is a white wire and a black wire painted white coming out of the wall.
2 questions:
Why is the wire painted white and do I assume that it is the hot wire?
 
Sponsored Links
  #2  
Old 01-29-07, 06:20 AM
Member
Join Date: Sep 2003
Location: Central New York State
Posts: 13,973
Never assume anything. Electricity can and does kill people.

In the US, a white wire indicates a grounded conductor, most often called a neutral or a return.

I would not even hazard a guess about this. Possibilities include paint from when the walls were painted, or someone not knowing what theyh are doing.

Use a voltmeter or a two wire tester to determine which wire is the hot wire and which is the neutral. If the black wire is not the hot wire, then I would investigate the switches and all of the wiring involved to understand what is going on, and make any necessary fixes.
 
  #3  
Old 01-29-07, 07:49 AM
Member
Join Date: Sep 2000
Location: United States
Posts: 18,497
Code does not permit a black wire to be painted white. In almost all cases, this is merely some drywall texturing or wall paint that accidentally got on the wires. But, as Bob says, never assume anything.

If this wire is intentionally painted, then all bets are off, as this is evidence that some unqualified person has been messing with the wiring.
 
  #4  
Old 01-29-07, 07:58 AM
Member
Thread Starter
Join Date: Jan 2007
Posts: 9
I just checked with a continuity tester and the black wire (with white paint) is definitely the hot wire. And as I look closer it does NOT look like it was intentionally painted. So, all is well and thanks for the advice.
 
  #5  
Old 01-29-07, 08:15 AM
Member
Join Date: Sep 2003
Location: Central New York State
Posts: 13,973
A continuity tester will tell you nothing. You need a voltage tester.
 
  #6  
Old 01-29-07, 08:29 AM
Member
Thread Starter
Join Date: Jan 2007
Posts: 9
I used the wrong term....I used a 2 wire voltage tester
 
  #7  
Old 01-29-07, 08:33 AM
Member
Join Date: Sep 2003
Location: Central New York State
Posts: 13,973
That's better. A two wire voltage tester will help you find the hot wire if you test each wire against a good ground, such as a properly grounded metal box, a properly grounded ground wire, or a metal pipe in your house, etc.
 
  #8  
Old 01-29-07, 08:39 AM
Member
Thread Starter
Join Date: Jan 2007
Posts: 9
Thanks
I also have a multimeter. I've only used it to test resistance. Can I use it to check voltage? If so, what setting do I use?
 
  #9  
Old 01-29-07, 08:41 AM
Member
Join Date: Sep 2000
Location: United States
Posts: 18,497
Use the AC volts setting. The multimeter came with instructions. Read them. If you've lost them, I'm sure google can find some.
 
  #10  
Old 01-29-07, 08:54 AM
Member
Join Date: Sep 2003
Location: Central New York State
Posts: 13,973
An analog meter is better to use than a digital meter. A digital meter is susceptible to phantom voltage, which can be confusing unless you know what it is and how to ignore it.

In addition to setting the meter for AC volts, you may also have to set the voltage scale. When discussing residential electricity, a setting of 300 volts ac is usually correct. That will allow you to see 0 volts, 120 volts, or 240 volts.
 
  #11  
Old 01-29-07, 09:31 AM
Member
Join Date: Sep 2000
Location: United States
Posts: 18,497
If all you want to do is see which wire is hot, that $2 two-wire neon voltage tester is the perfect tool. Leave the multimeter in the drawer.
 
  #12  
Old 01-29-07, 09:33 AM
Member
Thread Starter
Join Date: Jan 2007
Posts: 9
Sounds good...you guys are great!
 
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
Display Modes