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Is there a way to TEE into EMT without cutting the existing wires inside?

Is there a way to TEE into EMT without cutting the existing wires inside?


  #1  
Old 10-14-11, 05:27 PM
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Is there a way to TEE into EMT without cutting the existing wires inside?

It's hard to explain, I have a long conduit that I want to tee into but there is existing wires inside. I am trying to avoid cutting the wires inside to make a splice.

If I cut the EMT with a cutter, and if I have enough slack in this EMT pipe to pull the conduit apart a few inches, is there some sort of conduit body / box that I can connect to this to "TEE IN" another EMT?

I am thinking may be there is a box or conduit body that can split in half, and will enclose the existing wires when put back together.

Is there such a thing?
 
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Old 10-14-11, 06:58 PM
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No.

Short answer, but I need 25 characters.
 
  #3  
Old 10-14-11, 08:15 PM
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Does your local code require conduit? Your projects would be a lot easier without EMT.
 

Last edited by ray2047; 10-15-11 at 06:40 AM.
  #4  
Old 10-15-11, 12:18 AM
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He's using EMT, did you perhaps mean ENT? Of course ENT (electrical non-metallic tubing is STILL conduit.
 
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Old 10-15-11, 04:58 AM
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Originally Posted by Furd View Post
He's using EMT, did you perhaps mean ENT? Of course ENT (electrical non-metallic tubing is STILL conduit.
Or possibly without?

I don't like the 25 character minimum.
 
  #6  
Old 10-15-11, 06:41 AM
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Oops. Yes guys without.

....................
 
  #7  
Old 10-15-11, 06:58 AM
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No conduit is not required by code here, but all the older homes are in conduits.

This house I am renovating is all hard piped, even with recessed lights they pipe directly to the junction box of the fixtures.

and the existing pipes are not exactly EMT, they have the same diameter (outside) as EMT, but it is much thicker. I know because it takes almost twice as long to cut one of the existing pipes then a standard EMT.

What I ended up doing in the renovation is this.

- If it is inside a wall, interior or exterior, I will continue with EMT.

- Once it goes to the attic, if it's convenient I will switch to either NM or MC cables. I have done that a lot with a bath group. Takes the EMT to the attic, set up a junction box there, then spider out with the light fixtures, ventilation fan, scones etc... with MC cables or NM.

- If it's as convenient to use EMT in the attic such as connecting an existing EMT to another EMT, I will stay with EMT in those cases.

They even use EMT outside underground. I have since tore all those out (that I could locate) and replaced with PVC conduits.
 
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Old 10-15-11, 07:08 AM
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You could always pull the wires out to the nearest pull box or junction box, cut the conduit, put in a T, and then pull the wires back in.
 
  #9  
Old 10-15-11, 08:24 AM
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Originally Posted by Justin Smith View Post
You could always pull the wires out to the nearest pull box or junction box, cut the conduit, put in a T, and then pull the wires back in.
Or start abandoning the conduit wherever possible and using NM-b.*

*Local code permitting.
 

Last edited by ray2047; 10-15-11 at 11:46 AM.
  #10  
Old 10-15-11, 11:36 AM
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...and the existing pipes are not exactly EMT, they have the same diameter (outside) as EMT, but it is much thicker.
Perhaps IMC (intermediate metallic conduit)? IMC has a wall thickness about half-way between RMC (rigid metallic conduit) and EMT. IMC IS acceptable for underground usage and it can also be threaded.
 
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Old 10-15-11, 09:37 PM
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Originally Posted by Furd View Post
Perhaps IMC (intermediate metallic conduit)? IMC has a wall thickness about half-way between RMC (rigid metallic conduit) and EMT. IMC IS acceptable for underground usage and it can also be threaded.
Possibly. I don't know the terminology. I do know it is not rigid conduit because they did use rigid conduit in one spot and I had to use a special transition connector to EMT.

These conduits have the same outer diameter as EMT, the color is more like a light gray instead of a shinny silver like EMT. In fact, during demolition I dismantled several roomfuls of them and have a whole pile of them (and connectors) in my garage, which is good because as I rewire I have tons of these to reuse, and they are more solid then the new EMT I get.
 
  #12  
Old 10-16-11, 06:44 AM
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These conduits have the same outer diameter as EMT, the color is more like a light gray instead of a shinny silver like EMT
They might just be old EMT conduits. Older EMT usually is more gray in color and generally lacks the shine of new EMT although it would have had to be protected to not be rusted, like in your attic and walls. There may have been a diference in the alloys used years ago too, but I am not sure. The older EMT conduits I have seen generally had the old indenter fittings on them which are no longer allowed.
 
  #13  
Old 10-16-11, 07:00 AM
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Butt Splice Connectors

I have a situation I just do not have enough "slack length" to use a wire nut. I have to cut an EMT conduit using a tube cutter, then push the ends apart to insert a box in order to TEE in additional conductors.

I also have to cut the existing wires in the conduit and splice them back together. Two of the existing wires have very little slack, and the upstream and downstream JB are also difficult to access to pull new wires easily.

I think my best bet is to cut the two wires and butt splice them together.

What is the best type of butt splice connector to use in this case for #12 stranded wires? I saw the regular nylon ones, the heat shrink ones, then there are some that is crimped and have a solder ring in the middle, as well as some with adhesive inside. Which is the safest and strongest?
 
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Old 10-16-11, 08:05 AM
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What is the best type of butt splice connector to use in this case for #12 stranded wires? I saw the regular nylon ones, the heat shrink ones, then there are some that is crimped and have a solder ring in the middle, as well as some with adhesive inside. Which is the safest and strongest?
They all would work. For 12 you use yellow.
then there are some that is crimped and have a solder ring in the middle
I would personally use these.
 
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Old 10-16-11, 08:07 AM
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The code requires at least 6" of free conductor in the box. You would not have enough conductor length after T-ing the conduit.
 
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Old 10-16-11, 08:15 AM
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Just wondering, don't know if it was suggested...but why not cut a section out leaving enough wire for splicing then put in 2 boxes with new wire between them?
 
  #17  
Old 10-16-11, 08:20 AM
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Originally Posted by pcboss View Post
The code requires at least 6" of free conductor in the box. You would not have enough conductor length after T-ing the conduit.
But these wires are just pass through wires. I am inserting a new box into an existing conductor and trying to treat the old wires as best I can.

Seems using a butt splice connector would be the best given the situation.

If I need to create 6" of "free conductor" just for the sake of it, then I will have to put in two splices, to create an additional "weak point" and there is a chance of one of the two splices being partially hidden back into the conduit instead of being visible right in the middle.

I understand the reason for code being the free conductor to provide slack for future modifications, but in this case, it seems to add unnecessary congestion to the box.

In the wiring I have seen in this house, when wires simply pass through JB they seem to have very little slack, they didn't come in, do two extra loops in the JB, then leave. Now that may be because 40 years ago the code is different from today.
 
  #18  
Old 10-16-11, 09:33 AM
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The "slack rule" applies to splices and attachments, not continuous uninterrupted conductors.

In the wiring I have seen in this house, when wires simply pass through JB they seem to have very little slack,
 
  #19  
Old 10-16-11, 10:28 AM
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Your "Butt Splice" thread has been merged with your original one on this topic!

What you are proposing is against code:



*You need at least six inches of slack on each conductor inside a box.

*You are only able to use approved connectors of any type and you may have difficulty finding butt connectors that are. (Automotive connectors will not cut it even if they have a voltage rating higher than 12).

*Using a tube cutter is not generally considered a recommended practice for EMT, especially with conductors in it.
If you do use a tube cutter you need to fully de-burr the EMT and you would not be able to do it without risking damage to the conductors.

There is more but I think you have enough info steering you in the right direction.
We try to only offer correct, lawful advice and your planned coarse is not what any here would recommend.
It is good that you come here looking for guidance but you would be expected to do what any licensed trades-person would do.........not the illegal shortcuts you propose.
 
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Old 10-16-11, 10:42 AM
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I'd do what Gunguy suggested.
Just wondering, don't know if it was suggested...but why not cut a section out leaving enough wire for splicing then put in 2 boxes with new wire between them?
 
  #21  
Old 10-16-11, 07:54 PM
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Originally Posted by CasualJoe View Post
They might just be old EMT conduits. Older EMT usually is more gray in color and generally lacks the shine of new EMT although it would have had to be protected to not be rusted, like in your attic and walls. There may have been a diference in the alloys used years ago too, but I am not sure. The older EMT conduits I have seen generally had the old indenter fittings on them which are no longer allowed.
I looked closer at these conduits, they have markers on them, a "tic" every inch or so. It says "GUIDE-LINED", then further down "INCH MARKED" then further down "ELECTRUNITE".
 
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Old 10-16-11, 10:26 PM
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IDEAL makes butt splices rated at 75 celsius/600 volts and they are yellow. They are U.L. listed for copper only. Ideal does not make automotive connectors
 
  #23  
Old 10-17-11, 04:22 PM
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Originally Posted by MiamiCuse View Post
I looked closer at these conduits, they have markers on them, a "tic" every inch or so. It says "GUIDE-LINED", then further down "INCH MARKED" then further down "ELECTRUNITE".
That would be EMT, "Inch Mark" EMT is still available today.
 
  #24  
Old 10-17-11, 06:06 PM
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Originally Posted by GregH View Post
What you are proposing is against code:



*You need at least six inches of slack on each conductor inside a box.

*You are only able to use approved connectors of any type and you may have difficulty finding butt connectors that are. (Automotive connectors will not cut it even if they have a voltage rating higher than 12).

*Using a tube cutter is not generally considered a recommended practice for EMT, especially with conductors in it.
If you do use a tube cutter you need to fully de-burr the EMT and you would not be able to do it without risking damage to the conductors.

There is more but I think you have enough info steering you in the right direction.
We try to only offer correct, lawful advice and your planned coarse is not what any here would recommend.
It is good that you come here looking for guidance but you would be expected to do what any licensed trades-person would do.........not the illegal shortcuts you propose.
I understand and I am trying to do everything to code, but in this case I am between a rock and a hard place.

I have a series of recess lights that runs along the outside of the house, and I am adding a security light somewhere in the middle of the run. Physically it is at a corner, but it is the middle of the run of a series of recessed lights.

I need to tap a new hot and neutral conductors into the EMT pipe for the recessed lights because it goes by just twelve inches away. It is impossible to run new wires because it goes through "zones" of inaccessible areas and various wood framing is in the way.

The soffit is made of T1-11 wood panels. I used a circle cutter to cut a hole 7" in diameter, I can get to the wiring to the new security light, and the pipe of the recessed light passing by. I would have to access it from below. I can cut the EMT pipe in two, and two of the existing conductors I have enough slack to make a splice, and two of them I don't if I insert a 1900 box inline between the pipe ends.

As far as de-burring, it is not a problem, the wires would be cut right there anyways, I can de-burr the inside and outside without much trouble, then pull the wires back out.

I realize I need 6 to 8 inches of each conductor in the box. I guess the question is, if I butt splice the two wires with little slack, does this rule still apply? or can it be considered "continuous and uninterrupted wires"?

What I planned to do is where the cut out hole is, I will mount a new remodel recessed light, then the junction box will still be considered "accessible".

I can replace the wiring going downstream, as I have to open the junction boxes downstream to feed the new wire through anyways. What I don't want to do is to access the box upstream, because that light is 16 feet off the ground, and the JB for it is may be a foot higher on the inside.

A question on the 6" slack question. Since I pulled the wires and some of the wires I was able to get some slack, then it has to mean the slack came from the next and the previous boxes. If the next box has 10" of slack, and I pulled out 6", now there is only 4" left in that box. So for the code compliant electricians I have a question, if you pull a few inches of wires out of a conduit, in order to ensure you are still code compliant, you always go to the other side of the conduit, open the box, and make sure your pulling did not decrease the slack in that box to less than 6", right? If it is less than 6", what do you do? Do you forget it and say it's not practical? Do you feed a new wire a bit longer? or do you insert a new JB just to splice in the additional length?

That's kind of what I am struggling with, because it is going to be very tricky to mount two JBs from below through a 7" hole for the purpose of creating some 6" of slack in two wires.
 

Last edited by MiamiCuse; 10-17-11 at 08:00 PM.
  #25  
Old 10-17-11, 07:49 PM
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If the wire is cut/spliced, you need 6" of free wire.

Pull the wires out of the pipe back to one can. Cut the pipe and add your box. Repull in the wires by either pulling them trough the box or stopping them at the new box. Push any new wires from the new box to the existing can.
 
  #26  
Old 10-19-11, 07:39 AM
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OK now I think I am in trouble.

I don't really like the idea of putting up two junction boxes nearby just for the sake of creating wire slack. I think for whoever that follows my work in the future would scratch their head, what it is for, and effort wise, it will be more than pulling new wires that is 8" longer.

So I bite the bullet and got up high to the light 16' in the air, was able to westle it out, got to the junction box behind it. I opened it and saw the "short" wire. Note that this is done with me on an extension ladder looking up with a flash light, this is not fun. What I found is that this wire is also short. What I mean is this short wire is so short the wire nut is at the knockout hole. At least on the other side I had more like 2", and it is more than likely I was the one that pulled the wire nut in tight as I tried to create slack on the other end.

So I was kind of glad because now I am going to solve this problem on both ends, once and for all.

What I did was I twisted the old wire (solid) and the new wire (stranded) together there, then went back down to the original JB location to pull the new wire in using the old wire as I didn't want to pull from a high spot on a ladder.

I pulled about eight feet or so of the old solid wire and it stuck. I tugged it harder and it's not moving.

There are 4 other wires in this conduit, all old #12 solid copper wires.

I stopped at this point. As I Didn't want to proceed without some advice. My hunch says to go up and pull the new wire back out and hopefully will put the old wire back in place. Or should I pull the old wire as hard as I can? I am thinking the old wire being solid is tangled up around some elbow.
 
 

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