conduit touching another conduit

Reply

  #1  
Old 02-27-14, 10:48 AM
Member
Thread Starter
Join Date: Dec 2013
Posts: 284
Received 0 Votes on 0 Posts
conduit touching another conduit

Is it code compliant if one piece of emt is touching another piece of emt?

Is that bad practice? Ie grounding etc?
 
Sponsored Links
  #2  
Old 02-27-14, 11:24 AM
ray2047's Avatar
Member
Join Date: Mar 2006
Location: USA
Posts: 33,597
Received 13 Votes on 11 Posts
In commercial installation you often have multiple runs of conduit fastened to Unistrut. The Unistrut is metal and the bracket is metal with no insulator so you could say conduit electrically touching conduit is the norm and certainly not a code violation. In fact code says when you have multiple branch circuits in the same junction box all grounds must be connected together.
 
  #3  
Old 02-27-14, 12:24 PM
Member
Thread Starter
Join Date: Dec 2013
Posts: 284
Received 0 Votes on 0 Posts
I see, so even if they are on different circuits it is alright in regards to grounding too. This is in a building that relys on the mechanical ground of the conduit system.
 
  #4  
Old 02-27-14, 12:41 PM
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 18,493
Received 33 Votes on 25 Posts
ALL metallic parts in a building that might become energized, even under fault conditions, are supposed to be bonded and ultimately back to the earth. In other words, the conduits are supposed to be "connected" together in an electrical sense. the only thing to be concerned about is if the two conduits are rubbing rather than being stationary. Rubbing can wear a hole in the conduits over a period of time.
 
  #5  
Old 02-27-14, 01:09 PM
Member
Thread Starter
Join Date: Dec 2013
Posts: 284
Received 0 Votes on 0 Posts
I was thinking of some scenario where there was a ground fault and some might be looking for the problem on the wrong circuit... if that makes any sense.

Anyhow, thank you.
 
  #6  
Old 02-27-14, 02:20 PM
Member
Thread Starter
Join Date: Dec 2013
Posts: 284
Received 0 Votes on 0 Posts
Another thing...

I have to run emt in my basement from the ceiling which is exposed joists. I was able to get in one circuit with only some conduit touching. However, the other one has to go across copper pipe. Problem is the copper pipe is slightly lower than the joists bottoms where I intended to strap my emt too.... I really don't want to strap the emt tight to the copper plus the dissimilar metal thing cant be good.

Any idea how to tackle something like this? Essentially I have to get emt lower than the water pipes but the water pipes are sticking out lower than the joists in spots.
 
  #7  
Old 02-27-14, 04:41 PM
pcboss's Avatar
Forum Topic Moderator
Join Date: Jul 2002
Location: Maryland
Posts: 14,963
Received 34 Votes on 29 Posts
You would make a saddle bend in the EMT.
 
  #8  
Old 02-27-14, 06:07 PM
Mr.Awesome's Avatar
Member
Join Date: Oct 2013
Location: Canada
Posts: 592
Received 0 Votes on 0 Posts
Good call on the copper pipe.
When I worked maintenance, an office area got renos and the plumbers and electricians butt heads over who was going to have to move some runs in one area of the ceiling. Neither side caved and the result was a piece of EMT bucked right against a bare copper pipe. A few months later, a hole had been eaten in the copper pipe and part of the offices flooded.
Never mix dissimilar metals.

pcboss gave the best answer. Check this page out.
Offset Bends
 
  #9  
Old 02-28-14, 05:32 AM
Member
Thread Starter
Join Date: Dec 2013
Posts: 284
Received 0 Votes on 0 Posts
Wow, you had to mention it. Upo closer look I found one place where a 3/4 copper is touching a 3/4 rigid conduit.

Obviously I cannot move either. What can I do to separate this metals, theres hardly any play in the pipes.. perhaps enough to wrap tape around the conduit?
 
  #10  
Old 02-28-14, 07:17 AM
ray2047's Avatar
Member
Join Date: Mar 2006
Location: USA
Posts: 33,597
Received 13 Votes on 11 Posts
I found one place where a 3/4 copper is touching a 3/4 rigid conduit.
Slip a piece of rubber gasket (or inner tube) between them, wrap around, secure with wire ties
 
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
 
Ask a Question
Question Title:
Description:
Your question will be posted in: