So, I am going to install this subpanel. 6 ga individual wires, 3/4"
conduit. about 60 feet, 3 turns. Should I install conduit first and
fish wires, or keep pushing wires through every conduit piece as I am
installing? I am leaning towards the latter, but need some opinions,
Are they long-radius bends, or tight turns?
Put up all the conduit first, but don't strap it down tight in case you
need to take it apart if you have trouble running the wires.
Two #6's and two #8 will be a lot easier than four 6's. I'm not sure if
you can put four 6's in a 3/4" conduit. I've pushed three 6's in a 3/4"
and it was pretty tight. (If you use #8 wires, they have to be the
right color; white neutral and green ground.)
Use lube and you should be able to push the wires thru, but I've never
pushed more than 20 or 30 feet -- sometimes they hang at the couplings.
I've done that before many years ago, but if I were to do it again I
would always run a ground wire; maybe a bare stranded #8. I don't trust
the conduit joints to stay tight -- unless you are talking about rigid
or intermediate metal conduit (threaded connectors).
All you really need for a neutral is a #8. The grounded conductor of a
120/240V circuit that only carries the unbalanced current is allowed to
be one size smaller than the hot conductors. But if you want to run
three 6's, there's nothing wrong with that. I'm pretty sure four 6's is
too full for a 3/4" conduit, but three 6's and a 8 is OK barely.
I have two sixes with an eight gauge neutral for my 60A garage feeder,
and the chickenshit inspector that gave me grief about *everything* else
noticed it and thought it was just fine.
You might want to use an "entrance ell" for the last turn. I have
trouble pushing or pulling the wire thru more than 2 bends. You can
take the back off the entrance ell and use it as a pull point.
Thanks. Great point about the neutral wire, I wish I could think about
it earlier. In fact, what I really need for a neutral is a #10 at most
(20 amps). I could save a bunch. Maybe I will try to sell my neutral
wire on ebay.
No, you need a 6 or an 8 if you want it to be kosher.
If you have the wire already, use it. Just buy some 1" conduit instead
of the 3/4". And don't trust the conduit to be your ground unless it
has all threaded connectors, "grounding bushings", etc.
I do not believe a #10 neutral is permitted with #6 feeders. Codes are very
specific about permissible conductor and conduit sizes and it rarely is
advisable to do otherwise. I think you will need to pull your conductors
thru the conduit with a fish tape.
Best Regards, Don Young
This is Turtle.
I run your 2 # 6 wire and a # 8 Green or White ground wire and it says to use 1"
conduit but you can cram it through it but it is just hard to do so. Now Also it
says it is not suppose to be used this way and doesnot meet the NEC spec.s. Go a
head if you have good homeowners insurance I guess.
Now you can still put 3 # 6 through a 1" conduit and be legal.
It does depend on what kind of wire. You can run more THHN wires than
you can TW or R-whatever. But I would use 1" for a long run with 3
sixes. (I may go dig around in the garage and see if I can find my
maximum conduit fill tables.)
3/4" EMT is legal for four #6 AWG THHN wires. When you say three turns
do you mean three 90 degree bends through which you will pull the wire
or do you mean two ninety degree bends and one LB as you indicated
earlier? What made you decide to go with EMT instead of the cheaper and
easier SER cable? Did you consider running Type MC metal clad cable to
get much of the physical protection of EMT with most of the ease of
installation of cable?
Even with three ninety degree bends it should not be a tough pull. Just
use a quart bottle of pulling lubricant. The US NEC requires that a
conduit run be completed before the wire is pulled. Experience has
shown that the conductors are far more likely to be damaged if they are
inserted into the conduit as it is assembled.
[300.18 Raceway Installations.
(A) Complete Runs. Raceways, other than busways or exposed raceways
having hinged or removable covers, shall be installed complete between
outlet, junction, or splicing points prior to the installation of
conductors. ...] copyright 2002 National Fire Protection Association
Here's a raceway fill calculator that I found:
Four sixes is right at the maximum allowed fill for 3/4 EMT. It would
be a *very* difficult pull. Three #6 THHN's should be OK. Three #6
THHN's plus a bare stranded #8 ground, or two 6's and two 8's would be
Subject: Re: fishing 6 gauge wires through conduit
=> Ignoramus14233 <= wrote:>Thanks. Do you have some reference material that I could check? Thanks
Here is a conduit fill chart:
For some strange reason that I can not understand, multiple pulls are
against code. I have no idea how they'd know you did it or why it is
a bad idea.
However... the price of conduit is not all that different between 3/4
and one inch or 1.25 inch. It makes things a hell of a lot easier if
you use bigger conduit. Also, those "sweep bends" (not sure if that's
the name) are easier than a right angle adapter. Yes, it takes two
couplers and a sweep rather than a single adapter, but it's sure easier
pulling wire through it.
The first time I ran power down to my barn, I used 3/4 PVC conduit and
10/2 UF wire inside it to protect from rocks. The next time I used
6/3UF and 2.5 inch PVC. Never use "just big enough" wire. Actually,
I could have used 10/3 but if I had to redig the trench, why not put in
a huge feed? I never wanted to do this again.
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