Problems after replacing metal box

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  #1  
Old 03-03-11, 01:00 PM
R
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Problems after replacing metal box

Good afternoon,
I am looking for help with a problem as I am a total newbie to electrical projects.

Here is the scenario: I had an existing metal box which has metal conduit attached to it from bottom and top. Bottom contains the hot wire which then feeds recessed lights on top.
I replaced the existing wall switch with a new one and later found that it would not fit in the existing metal box. I bought a deeper plastic box and replaced the metal box with it. After this, the recessed lights did not turn on. I noticed that my "pen" voltage tester now detects current throughout the metal conduit leading up to the recessed lights. I am assuming that by removing the metal box, I lost ground? Problem is that there are only two wires and no ground wire in the conduit.

Any clues on what is going on?

Thanks,
Angel
 
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Old 03-03-11, 02:08 PM
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You can not replace a metal box with a plastic box if metal conduit. It is not code compliant.

I noticed that my "pen" voltage tester now detects current throughout the metal conduit leading up to the recessed lights.
Non-contact testers are prone to false positives.

I am assuming that by removing the metal box, I lost ground? Problem is that there are only two wires and no ground wire in the conduit.
That is why a plastic box is not code compliant.
 
  #3  
Old 03-03-11, 03:06 PM
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Originally Posted by rivers001 View Post
Bottom contains the hot wire which then feeds recessed lights on top.
Did it contain only the hot wire, or were there other wires too? What did you do with them?

Also as Ray said, you need to change the box back to metal. Metal boxes are available in a variety of depths with a variety of mud ring depths also.
 
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Old 03-03-11, 05:39 PM
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Yes, it contained only the hot wire.

Based your responses it seems that I will need to change thebox back to metal.
 
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Old 03-03-11, 07:44 PM
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I replaced the existing wall switch with a new one and later found that it would not fit in the existing metal box.
I am curious why if there was a switch in the original box why a replacement switch wouldn't fit. I am thinking you have done a lot of work for nothing.
 
  #6  
Old 03-04-11, 09:56 AM
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Originally Posted by rivers001 View Post
Yes, it contained only the hot wire.
Now that is a major problem. The conduit needs to have a complete set of circuit conductors (hot and neutral) or be a switch loop (hot and switched hot). I can't think of any situation where a conduit with one conductor would be safe or legal.
 
  #7  
Old 03-04-11, 01:46 PM
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Wow, the conduit is not only the ground, it is the neutral as well. Danger Will Robinson! And also not legal.
 
 

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