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I have a craftsman contractor table saw and I use it in an out building that the previous owners built. The saw has a 1 horse capacitor start motor and every time I switch it on all the lights in the shop dim to dark and they slowly flicker back on till the saw gets up and running. I'm also sure that the saw is not running at it's full potential. The wiring that goes out there underground is only 14 guage and it runs for about 85 feet underground. Before anyone tells me to run a new line, I have to say that I really don't want to put any more money in to this house. I am stuck in a bad loan with an underwater mortgage to boot and so far I can not get out. So sinking more money into something that I may lose isn't really appealing. Does anyone have any other suggestions? Do you think the wire should be able to handle the load? I'm just not sure. BTW… the power to the shop is also running through a standard light switch in the garage that controls the whole works. Could this be limiting flow if it is an low amperage switch?
 

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At 85 feet and 14 gauge, you;re really draining the pipe! Motors and other inductive loads need a lot of startup current and your pipe is both too skinny and too long. If you don't want to spend any money, the best you can do is to move the motor closer to your panel (shorter wire). And to matters worse, you may have a lot of wire between the panel and that light switch.
 

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Go buy a 100' 12ga ext cord for the saw and leave the lights on the old wire.
That does 2 things, keeps your saw running better and also if ya blow a breaker with the saw, yer not in the dark.

Take the cord when ya move on.
 

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I concur on the 10 ga. extension cord. This is the very least you should do!

You mention that the feed to the outbuilding is coming off an existing light switch - who knows what else is on that circuit or how much wire length is between the circuit box and that light switch - it all adds to the total distance. Since your lights are dimming when running the saw, you obviously have an overload. If you keep using it as configured right now, chances are that you are gradually damaging the insulation in the existing house wiring from overheating. Whether you like your home or not, I don't believe you want to burn it down and that is a very real possibility. Whoever ran the outside line off the light switch obviously knew nothing about the National Electrical Code! The line was probably meant to provide lighting to the outbuilding and a utility outlet, not to provide current for major current-drawing equipment.

I can't stress enough - use the wiring to the outbuilding only for lighting and low amperage devices. If you want to run your table saw, etc. out there, you need to either run an entirely new line from circuit breaker panel, underground (following applicable local codes), to the outbuilding. Actually you should run two - one for lighting and one for the power equipment. The only other option is as has been recommended - a 10 gauge extension cord.

Jim
(Electronics/Computer Tech - 35 years)
 

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Discussion Starter · #8 ·
Great Idea. A little bit of a hassle but a lot cheaper and safer to boot. I was worried about the safety of this wiring the way I'm using it. Thing is, the guy built the shed with outlets in it and I think he did welding out there. That tells me that he meant it to be used for more than lights. The neighbor told me that he did his own wiring and screwed up quite a few things. I've had to fix quite a few reversed outlets and other wiring no-no's that he did. Sucks that someone else's stupidity is leading to so many problems for me. Where should I plug in the extention cord if it will still be running through the household wiring? Close to the panel?
 

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Discussion Starter · #10 ·
Well, It's about 110 feet to the shed from the garage door. So It's probably another 75 to the box. Not good. I think I might be moving into the garage…. Guess we'll see. The cord would have to be probably two 75 footers and man what a pain to set those up when I want to work. I would end up never working on anything.
 

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Your 1 hp motor is drawing close to 16 amps on 120 volts; therefore, #10 over 110 feet is the minimum size cord you should use. That should keep your running current within the 5% drop allowed by code. Your lights may still dim when you start the saw. The best thing you could do is go to 220, but I doubt is your 1 hp saw motor has that optioin.
 

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I was wondering when Topamax would get in on this.

I would listen to him and as a contractor I would be using him for all of my electrical work if we were in the same town.
 

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When I set up my under-house garage as a workshop, I ran new 20A circuits, one down the right side and another down the left side of the garage. Another circuit feeds the lights. If you are going to move to your garage, as I would highly recommend, you may want to check to see what circuits you have available there. Make sure your outlets are on their own circuit, not sharing with other rooms and equipment.

Jim
 

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I had a very similar situation. I ran two 10 ga. lines and one 12 from my box, about 90 feet, underground through plastic conduit.

In addition to dimming lights, with that low voltage you are running the risk of ruining some power tools.
 

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Hey Skywalker,
Here's an off the wall suggestion that won't put any more money into your house. Buy a generator. It will be nice to have power when the lectricity goes out, you can run your saw as well as other power hungry tools, you can have electricity when you go camping and you can take it with you when you leave.

You might be able to buy one used and if you don't want to keep it, sell it later.
 

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Discussion Starter · #16 ·
Huh, interesting, Can they put out enough power for a saw like that? I assume so or you wouldn't suggest it I guess. Might be a little loud and I work at night sometimes but it's a possibility. Thanks!
 

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Discussion Starter · #17 ·
Okay I've decided to put a little money into the house and go for it on this one as I need a useable shop space.
Here's my plan:
New 50 amp 2 pole breaker in the main panel,
10-3 indoor wire ran to outside into sched 40 down into the ground,
Run the same 10-3 indoor wire all the way out to the shed inside the sch 40 that will be sealed 24" under ground,
Come up under the shed and terminate into a sub panel which will go to several breakers for different outlets,

Can I use indoor cable inside of conduit like described or does it HAVE to be UF type?
Can I use the ground from the main panel alone in this way?
If I can use the indoor cable perhaps I use 10-2 and put a grounding rod at the sub panel out at the shop using the ground wire inside the 10-2 for the nuetral?
Any help would be appreciated.

Thanks
 

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Usually you run individual wires in a pipe not romex (10-3). You should be able to fit 3 #8 (2 hots and a neutral) wires in 3/4 pipe. Terminate at a sub panel with 4 15 amp breakers. Take off from there. Have the sub panel grounded at the panel. (ground rod just outside #4 or so wire to it)

Again, don't run much at any one time. Change motors to 220/230 to split the load between 2 legs.
 

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Luke for a run that long on a 50 amp breaker 6 gauge wire is needed. I did something similar for my shop but only a 50ft run. I buried conduit and ran 6-3 romex from a 50amp 2 pole on the main box to a sub panel in the shop. With 50amps of "overhead" it splits into 1 15amp for general lighting, 1 20amp for my dust collector, and 1 20 amp for tool use. I'm no NEC expert but I know a sub panel must be grounded through the main panel DO NOT USE A GROUNDING ROD AT THE SHOP. Using 6-3 wire also allows me to have 220v service if I ever see the need for it. 6-3 romex is very stiff wire and I would recommend 2 inch conduit just for ease of pulling the wire through. I ran mine in 1 inch and found it to be EXTREMELY difficult. I chose romex because of my sources it was cheaper then running individual strands of 6 gauge wire. With that electric service ran to my shop when I turn on the saw with the dust collector running I just get a small flicker in the lighting. And the reassurance of heavy gauge wire lets me feel confident when running multiple high amperage machines. Good luck with wiring your shop (its a lot more work then it looks to be).
 

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FYI, Romex is not legal to pull in an underground conduit per the National Electric Code. You need UF or single condutors such as THWN.

A ground rod is required at the out building location, but a equipment grounding conductor can be run back to the main which I recommend. The equipment grounds are to be on a seperatte buss in the subpanel, not all on one as in yoiu main panel.

The seperate building reuires a single disconnect to cut all power.

It is your life and safety on the line. Get it inspected!!
 
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