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Posted By: akmaster Supported fittings - 06/07/13 10:12 PM
Here is a question that is probably been changed since I looked it up but if I have a 2" T, do I not have to come out with at least two trade size conduits unless the fitting is supported? I am thinking it is required that there be at least two trade size conduits exiting or the fitting had to be supported...I have a 2" T with two 1-1/2" and a 2" connected to the T.

Please quote article if possible.

thanks very much,

Greg
Posted By: HotLine1 Re: Supported fittings - 06/08/13 02:08 AM
Ak:
Try this from 2011, 314.23-(E)

"(E) Raceway Supported Enclosure, Without Devices,
Luminaires, or Lampholders. An enclosure that does not
contain a device(s) other than splicing devices or support a
luminaire(s), lampholder, or other equipment and is supported
by entering raceways shall not exceed 1650 cm3
(100 in.3) in size. It shall have threaded entries or have
hubs identified for the purpose. It shall be supported by two
or more conduits threaded wrenchtight into the enclosure or
hubs. Each conduit shall be secured within 900 mm (3 ft) of
the enclosure, or within 450 mm (18 in.) of the enclosure if
all conduit entries are on the same side.

Exception: The following wiring methods shall be permitted
to support a conduit body of any size, including a conduit
body constructed with only one conduit entry, if the
trade size of the conduit body is not larger than the largest trade size of the conduit or tubing:
(1) Intermediate metal conduit, Type IMC
(2) Rigid metal conduit, Type RMC
(3) Rigid polyvinyl chloride conduit, Type PVC
(4) Reinforced thermosetting resin conduit, Type RTRC
(5) Electrical metallic tubing, Type EMT
Posted By: akmaster Re: Supported fittings - 06/08/13 03:15 PM
Thanks John,
This is what I was looking for. I am interpreting this as meaning that the fitting is considered supported as long as ALL conduits are the same trade size as the fitting..

So no RE's...I.E. 2" T with one 2" and two 1" conduits unless it is supported within 3'?

Thanks

Greg
Posted By: akmaster Re: Supported fittings - 06/10/13 11:59 PM
Hi,
I am asking for a little clarification on 314.23-(E)...

Is this saying that only ONE conduit must be trade size?

I have a 2" T with a 2" RGS coming into the T and 3/4" and 1" conduits leaving the other two entries...

This article used to say at least two conduits had to be trade size...

Can someone clarify what is legal?

It seems to read that any conduit must be trade size of the fitting..

Thanks for your help.

regards

Greg
Posted By: gfretwell Re: Supported fittings - 06/11/13 02:55 AM
The easy answer is support it within 3' on either side of the conduit body (<100 cu/in) and it doesn't matter.

The exception allows you to virtually ignore the conduit body if it is the same as the raceway size and the raceway is supported properly. It is just a bump in the pipe that requires no special support.
As soon as you start hanging devices you are moving down to (F) and you need support at 18" from both sides or 12" if it is one pipe (d).
Posted By: akmaster Re: Supported fittings - 06/11/13 03:18 PM
Thanks Greg,
I understand your first sentence but the second is still bugging me..

If supported within 3' you can use any size conduit?

Thanks again...sorry for being hard headed!

regards,

Greg
Posted By: gfretwell Re: Supported fittings - 06/11/13 04:48 PM
Let's look at it again.

Quote
(E) Raceway Supported Enclosure, Without Devices,
Luminaires, or Lampholders. An enclosure that does not
contain a device(s) other than splicing devices or support a
luminaire(s), lampholder, or other equipment and is supported
by entering raceways shall not exceed 1650 cm3
(100 in.3) in size. It shall have threaded entries or have
hubs identified for the purpose. It shall be supported by two
or more conduits threaded wrenchtight into the enclosure or
hubs. Each conduit shall be secured within 900 mm (3 ft) of
the enclosure, or within 450 mm (18 in.) of the enclosure if
all conduit entries are on the same side.


The base article does not say "conduit body" at all so there is no "size" defined beyond "<100 cu/in".
This means it could be a Bell box if that was what you wanted to use and you could still support at it 3" from both sides or 18" if both conduits come from the same side.

It is when you get down to the exception for conduit bodies that the conduit size comes in.

Quote

Exception: The following wiring methods shall be permitted
to support a conduit body of any size, including a conduit
body constructed with only one conduit entry, if the
trade size of the conduit body is not larger than the largest
trade size of the conduit or tubing:
(1) Intermediate metal conduit, Type IMC
(2) Rigid metal conduit, Type RMC
(3) Rigid polyvinyl chloride conduit, Type PVC
(4) Reinforced thermosetting resin conduit, Type RTRC
(5) Electrical metallic tubing, Type EMT
Posted By: gfretwell Re: Supported fittings - 06/11/13 05:07 PM
There is one interesting ramification. The article does not say solvent welded so you might argue you could not use a PVC "glue in" enclosure that wasn't a conduit body unless it was otherwise supported. If you had a threaded entry box with male adapters on the PVC it would be legal according to the way the code is written.

Look for a proposal there.

The other significant thing is the conduit body exception removes the 100 cu/in restriction.
A 6" conduit body will exceed 100 cu/in but it can still be supported by 6" conduits at normal support intervals. You just can't use smaller conduits for support.
Posted By: akmaster Re: Supported fittings - 06/11/13 06:26 PM
OK Greg...thanks for the clarification... so say I have an FS box with an outlet in it..a 3/4 rigid from the top and 3/4 from the bottom...box is in free air..conduits threaded in and one hole strap within 3' of FS box...does the box need to be supported or is it considered supported by the conduits?

Posted By: gfretwell Re: Supported fittings - 06/11/13 07:00 PM
OK you changed the game a little when you put a device (other than a splice) in the enclosure.
Now you are in 314.23(F).
Your support, on both sides, now needs to be 18" or less.

Quote
(F) Raceway-Supported Enclosures, with Devices, Luminaires,
or Lampholders. An enclosure that contains a
device(s), other than splicing devices, or supports a luminaire(
s), lampholder, or other equipment and is supported by
entering raceways shall not exceed 1650 cm3 (100 in.3) in
size. It shall have threaded entries or have hubs identified for
the purpose. It shall be supported by two or more conduits
threaded wrenchtight into the enclosure or hubs. Each conduit
shall be secured within 450 mm (18 in.) of the enclosure.


I still would be more picky if you were talking about a receptacle. That box better not move when I grabbed it and gave it a twist.

Posted By: akmaster Re: Supported fittings - 06/12/13 01:55 PM
Thanks, I did that and it was tight.
Appreciate the help as always.

Regards
greg
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