Installing a Smaller EMT Conduit Into a Set-Screw Hub of a Larger Size

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britcollector

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I have an aluminum 1-1/4" EMT set-screw type-T fitting with (6) #6 and (18) #12 conductors passing straight thru. On the bottom leg of the ‘T’, I am diverting (6) of the #12 conductors. I want to use a ¾” EMT for this leg. Is there an approved way to connect ¾" EMT to a 1-1/4” set-screw hub of a fitting? Because of space constraints, I'd rather not use an intermediate pull box to make the transition. I can’t find any NEC reference, nor a manufacturer who makes an adapter. Thanks in advance!
 
Dennis Alwon

Dennis Alwon

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Use a reducing bushing. They make them in many different sizes


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britcollector

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Thanks for the quick answers!

Dennis: I can't use a threaded bushing because it's a set-screw hub.

kwired: I was looking into a short 1-1/4" and then reducing that, but can't find any reducing adapters (other than EMT to rigid). The only way I can see doing it is to use a pull-box and bring a short stub of 1-1/4" into it and then exit with 3/4". Besides it not being very pretty, I'm tight on room.
 
kwired

kwired

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britcollector said:
Thanks for the quick answers!

Dennis: I can't use a threaded bushing because it's a set-screw hub.

kwired: I was looking into a short 1-1/4" and then reducing that, but can't find any reducing adapters (other than EMT to rigid). The only way I can see doing it is to use a pull-box and bring a short stub of 1-1/4" into it and then exit with 3/4". Besides it not being very pretty, I'm tight on room.
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About only thing I expected to find as well. Then use reducing bushing to reduce the rigid side and an EMT connector threaded into it for your 3/4 run. If some inspector questions it maybe they at least let you use an external bonding jumper around it?
 
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britcollector

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Hi Rob -- Yup, I know a threaded body is the solution. I was trying to avoid having to eat the costs of having purchased 15 of the screw type T bodies I bought that aren't returnable. Oh well....
 
infinity

infinity

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britcollector said:
Hi Rob -- Yup, I know a threaded body is the solution. I was trying to avoid having to eat the costs of having purchased 15 of the screw type T bodies I bought that aren't returnable. Oh well....
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Sorry to give you the bad news. :oops:

We only buy the combination set screw/threaded conduit bodies for this reason.
 
480sparky

480sparky

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I can't claim to have even known of the existence of this 'set-screw condulet' fitting. All I've ever seen is threaded ones.
 
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britcollector

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Sparky, that's why I bought them...I got them for $6 each! I should have known that they were cheap because they were the runt of the litter! I'll sell them and get threaded ones. Live and learn!
 
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infinity

infinity

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Yup the combo type are the most versatile. I'm not a big fan of Topaz but that's what our supply house sells so that's what we use. Comes with the gasket and the cover.

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augie47

augie47

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I like K-wired's idea,.,,,,, short section of 1-1/4 conduit to an adapter (EMT to Female PT if available, or EMT to Male and a coupling) then install your bushing in that fitting.
 
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britcollector

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Little Bill: Yes...because I am running grounds for each circuit (sensitive CNC equipment) the number of current carrying conductors are fewer.
 
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