Power and phone lines for the shop - meeting the NEC

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Years ago, I actually owned a copy of the National Electric Code and kept up with it, as an electrical engineer in an industrial situation. I no longer work as an electrical engineer and I've never had to know much about residential applications, so I have some dumb questions.
I'm running a new power feed and two phone lines to my emerging shop. I've settled on running individual #6 power lines with a #12 ground. I'll run all of this through a 1" PVC conduit to get from the existing breaker panel outside to a point where I can bring the wires into the attic and over to the garage shop. I also will have a 4 conductor telephone-type wire. Its cleaner to run the phone line in the same conduit as the power, but I'm concerned about two things - electrical noise pickup and compliance with National electric code. As to the noise, I can always run the cable and if its noisy, just abandon it in place.
If you have any knowledge about NEC with regard to running phone lines and power in the same conduit, please let me know.
Yes, this is related to woodworking. The power will run a complete new set of tools - table saw, dust collector, jointer, drill press, planer, band saw, and coffee pot. The phone line will be used to call my woodworking friends when I get stuck with a problem in the shop.
Thanks in advance for your comments.
Bob
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You cannot run the telephone lines in the same conduit as the AC for your shop. I would run the ground wire as a #6 also. If the neutral fails and the ground carries the current it could burn.
: Years ago, I actually owned a copy of the National Electric Code and kept up : with it, as an electrical engineer in an industrial situation. I no longer : work as an electrical engineer and I've never had to know much about : residential applications, so I have some dumb questions. : : I'm running a new power feed and two phone lines to my emerging shop. I've : settled on running individual #6 power lines with a #12 ground. I'll run : all of this through a 1" PVC conduit to get from the existing breaker panel : outside to a point where I can bring the wires into the attic and over to : the garage shop. I also will have a 4 conductor telephone-type wire. Its : cleaner to run the phone line in the same conduit as the power, but I'm : concerned about two things - electrical noise pickup and compliance with : National electric code. As to the noise, I can always run the cable and if : its noisy, just abandon it in place. : : If you have any knowledge about NEC with regard to running phone lines and : power in the same conduit, please let me know. : : Yes, this is related to woodworking. The power will run a complete new set : of tools - table saw, dust collector, jointer, drill press, planer, band : saw, and coffee pot. The phone line will be used to call my woodworking : friends when I get stuck with a problem in the shop. : : Thanks in advance for your comments. : : Bob : :
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no it should not be in the same conduit, run a separate (small) conduit and run the phone, intercom, security and network cable in it.
the ground wire is NOT there to handle the load if the neutral "fails"
ask your electric supplier, he know the scoop for the local area. wire inspectors can, and do, set their own rules.
BRuce
Bob Gramza wrote:

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explicitly prohibited by the NEC, Article 800-52.

True, but he still should use a #6 or #8 equipment ground instead of #12.

-- Regards, Doug Miller (alphageek-at-milmac-dot-com)
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run the phone live seperate.......I needed my once in an emergency....glad I had a phone in the shop to call for help...it wasn,t ;wood related though, slip n fell on the icy drive n broke my ankle, the shop phone was the closest I could get too....have fun....
<BRuce> wrote in message

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Thanks for the reply, Bob.
Regarding your comment about the neutral, I want to be sure we are talking apples and apples. My plan is to carry three #6 conductors for 120/240 single phase service. The #12 was intended to be just an equipment ground, not a current carrying wire. Does the code require it to be same size? My existing panel would be in violation. I think its got 3 #2's coming in and what appears to be a #10 going to ground rod.
Best regards, Bob

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The other gentleman was correct in that it is not a current carrying wire. It can be a smaller. I do not know the gauge size the NEC calls for though. My book is long gone.
: > : Years ago, I actually owned a copy of the National Electric Code and : kept up : > : with it, as an electrical engineer in an industrial situation. I no : longer : > : work as an electrical engineer and I've never had to know much about : > : residential applications, so I have some dumb questions. : > : : > : I'm running a new power feed and two phone lines to my emerging shop. : I've : > : settled on running individual #6 power lines with a #12 ground. I'll : run : > : all of this through a 1" PVC conduit to get from the existing breaker : panel : > : outside to a point where I can bring the wires into the attic and over : to : > : the garage shop. I also will have a 4 conductor telephone-type wire. : Its : > : cleaner to run the phone line in the same conduit as the power, but I'm : > : concerned about two things - electrical noise pickup and compliance with : > : National electric code. As to the noise, I can always run the cable and : if : > : its noisy, just abandon it in place. : > : : > : If you have any knowledge about NEC with regard to running phone lines : and : > : power in the same conduit, please let me know. : > : : > : Yes, this is related to woodworking. The power will run a complete new : set : > : of tools - table saw, dust collector, jointer, drill press, planer, band : > : saw, and coffee pot. The phone line will be used to call my woodworking : > : friends when I get stuck with a problem in the shop. : > : : > : Thanks in advance for your comments. : > : : > : Bob : > : : > : : > : > : :
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Wrongo. If it is the first panel, the neutral does not need to be as big as the hot conductors. When it is a sub panel, it has to have 3 full sized conductors, and a separate ground, separate busses on the second panel, neutral insulated.
It does not have to make sense to you. It is the code, remember? <g>
--
Jim in NC



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Actually if you read 220.22 you only have to size the neutral to the "unbalanced load". If your sub panel is all 240v breakers with no neutral load you don't even need a neutral. As an inspector I would demand that the neutral was sized to the largest total number of single pole breakers on either phase. That could easily be bigger than the required size of the feeder "hots" though if this was a general lighting panel, loaded with single pole breakers so you default to "equal size". On the other hand if this is basically a 240v shop with a couple 120v circuits you could downsize the neutral. I still advise against it. The only logical reason you would do it would be a conduit fill issue with an already "in place" raceway system, you didn't want to dig up. Wire is cheap. The same is true with choosing a 3 wire feeder system over a 4 wire system. Lots of things that might work and may even be "hold your nose" legal are not the best choice.
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copper-clad aluminum equipment grounding conductors shall not be less than shown in table 250-95." [Article 250-95]
The table gives the following for copper wire:
*** Please note that more recent codes may have more restrictive requirements. In any event, though, this shows that your plan is clearly a code violation even under the 1993 NEC. Your service entrance isn't in compliance either, but it may have been at the time it was installed.
15A breaker, 14 ga wire 20A, 12 ga 30 thru 60A, 10ga 100A, 8ga 200A, 6ga [higher amperages omitted]

-- Regards, Doug Miller (alphageek-at-milmac-dot-com)
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Ah, facts I can use. So, since my service is #6 wires (55-60 amps depending on how you interpret the ratings), I need a #10 ground wire.
Bob

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On Tue, 28 Oct 2003 22:03:51 GMT, "Bob Davis"

Any special reason why yer runnin' the wire inside that pipe? You don't need to, ya know. There's easier and cheaper ways to accomplish what you want to do.
You might even want to just put a drop right at the garage.
Have a nice week...
Trent
Follow Joan Rivers' example --- get pre-embalmed!
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The run is from the main box inside the house to a detached garage. Part of the run is outside. I'm only putting the wire in pipe where its outside. I guess I just feel more comfortable with it being put inside of something and pipe is cheap.
Bob

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I appreciate all the replies. I'm at the stage where its easier to change and be safe, rather than try to get by. That's why I asked before I actually did the "cannot turn back" part of the installation.
In summary the suggestions/admonitions from the group:
1. Do not run the phone wire in the same conduit with the power. 2. Use a larger ground wire, suggested #6 or #8.
Since the phone wire does not have to be in conduit, I'll just run it outside parallel to the power conduit and hide it behind the conduit. In my area, that's typically how phone wiring is done (exterior grade phone wire stabled to the building).
Best regards, Bob

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Don't cheapen out -- drop a 1/2" or better 3/4" conduit next to the power line so that you can pull in phone, network, even cable TV or internet connection. You don't know what you will want/need down the road but you will be thankful for having that extra conduit available, especially if it travels underground for any distance. PS. If you are using PVC conduit, the voice/data lines should not be attached to or very close to the power conduit -- vinyl does not provide the shielding that steel conduit would -- keep them a couple of inches or more apart.

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I appreciate the wisdom of your remarks, Eric. Years ago, I had an experience working as lead engineer on a plant reconstruction. The electrical foreman taught me a lesson well remembered. I was busy specifying and buying materials and watching the budget. He told me to always buy conduit one or two sizes bigger than the code called for. He told me I'd eat up my dollars paying for labor soaping the cables and pulling it, including some broken wires on long, complex runs. An electrician will practically kiss you when the code says 40% fill and you go for 25% fill instead.
It seems silly that I know so much about the heavy stuff (high voltage, motor control centers, etc) and I'm as dumb as a skunk on residential wiring. I wish I could find my old copy of the code. It would be kind of fun to go through it for old times sake.
Bob

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find my old copy of the code. It would be kind of

Don't bother <g> The new code bears little resemblance to the current code.
--
Jim in NC



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On Tue, 28 Oct 2003 17:55:38 GMT, "Bob Davis"

You can find the code on the Internet, Bob.
Have a nice week...
Trent
Follow Joan Rivers' example --- get pre-embalmed!
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I've found where I can buy it. But I've googled all over the place looking for excerpts of it. Any help?
Bob
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You may find some interpretations on the net but the NEC is a copyrighted NFPA document and they are very protective of their property. You would have a better chance of keeping bootleg copies of Win/XP on your site than to keep the NEC up there for long.
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