More Amps to My Garage

[Chuck Schultz]

I currently have one 20 amp circuit breaker feeding my detached garage for all my tools. I can barely run two tools at the same time. I'm looking to add more amps to my garage, and I'm trying to find the most cost effective way to do this. I'd like to add a subpanel for the garage, but that would mean running new wire to the garage and burying it under the driveway and the garage? I've also thought about having another meter from the power company just for my garage.

Anybody have any ideas?

[Gary Max]

I went with a seperate meter----most of the light bills for the shop are less than $30.00----no AC or electic heat
Install the biggest box you can find and run 220 everywhere. I must have ten 220 outlets in the shop.

[Joe Hardesty]

Before deciding to add another meter, you may want to check your electric bill. Your price per KWH probably drops based on higher usage.

If you put in a second meter, your effectively working from zero and paying the highest rate for your shop each month. Running a sub-panel and using electricity from the main meter will get you cheaper electricity in an area that tends to us a lot.

Of course, it may not be a great deal of money and the convenience of a second meter may be preferable. Just offering the downside to the argument if it applies in your area.

[Jim O'Dell]

The other thing to check out is what rate will the second meter be billed at. Here, with Tex Electric, they would only do the second meter at commercial rates. I was lucky that TX having deregulated electricity, I could choose a different "provider" (actually read that as biller as all the electricity comes from the same line, same generating company) for the shop. My second line was installed by the previous owner, so that was already in place.
But if you can't choose a separate provider, check with your electric company now and see what rate it will be billed as. It may make doing a underground line as a sub panel a little more attractive. Jim.

[Dewey Torres]

The conduit run isn't as hard as it sounds. You should look into that option a bit more before you write it off. I had a 60amp sub installed in my old shop in VA for $500. It was done in a day and money well spent.

[Robert Pasuth]

Chuck, I have the same delima in CT. I now have 2 circuits and this is addequate for now. My father-in-law had a suggestion that I will do at some point. He said run (in my case) 10/3 direct burial wire from my house to the garage and put a 40-50 AMP subpanel in the garage. This will be a 240 Volts 40 amp panel. This would give 2 simultaneous 240 20 amp circuits, or 1 240 circuit and 2 120 circuits at the same time or any way you mix it, you now a multiple circuits at your disposal. And as stated before, you get the better rate for using more electricity. Good luck.

[Dewey Torres]

Might I also ask that you call it a shop vs a garage.;)

[Rollie Meyers]

Chuck, I have the same delima in CT. I now have 2 circuits and this is addequate for now. My father-in-law had a suggestion that I will do at some point. He said run (in my case) 10/3 direct burial wire from my house to the garage and put a 40-50 AMP subpanel in the garage. This will be a 240 Volts 40 amp panel. This would give 2 simultaneous 240 20 amp circuits, or 1 240 circuit and 2 120 circuits at the same time or any way you mix it, you now a multiple circuits at your disposal. And as stated before, you get the better rate for using more electricity. Good luck.


You are only able to use a 30 ampere overcurrent device for that use.

[Rob Russell]

Chuck, I have the same delima in CT. I now have 2 circuits and this is addequate for now. My father-in-law had a suggestion that I will do at some point. He said run (in my case) 10/3 direct burial wire from my house to the garage and put a 40-50 AMP subpanel in the garage. This will be a 240 Volts 40 amp panel. This would give 2 simultaneous 240 20 amp circuits, or 1 240 circuit and 2 120 circuits at the same time or any way you mix it, you now a multiple circuits at your disposal. And as stated before, you get the better rate for using more electricity. Good luck.


UF and USE pretty much have to be treated like regular NM cable and that includes the ampacity ratings. If you want a 40A subpanel, you need to run #8. If you want a 50A subpanel, you need to run #6.

If you want a subpanel that can serve both 240v and 120v loads, you need to run cable that has 3 insulated conductors + an equipment grounding conductor. For example, if you ran 8/2 direct burial cable, you would be able to do a 40A subpanel, but you would only be able to run 240v loads from it because you would not have a neutral.

[Chuck Schultz]

The conduit run isn't as hard as it sounds. You should look into that option a bit more before you write it off. I had a 60amp sub installed in my old shop in VA for $500. It was done in a day and money well spent.

Did you have an electrician come in a wire this up, or did you do it on your own? I'm pretty comfortable running cable and wiring, but for $500 or so, I've got other things I can spend my time on.

[David G Baker]

Chuck,
Get a couple of bids, you may find that it costs less than you think. Licensed electricians should be able to find paths to your work area that us amateurs can't see and make what seems like a complicated job very easy.

[Robert Pasuth]

Might I also ask that you call it a shop vs a garage.;)


OOPS, I usually call it the shop, and the wife breaks em off on me.

As for the wire guage I was obviously mistaken (sorry), I was trying to remember the specifics from my father-in-law. But you understand what was trying to be done. Just the idea to help and as usual I miss some of the specifics.

[Andy Pratt]

I think most companies charge a separate fee every month for a second meter. I know where I live it's basically as if I have two different properties, two separate bills and two separate feeds, even though both are off the same run from the power line. I will have a second meter anyway since it's for business and I need to know exactly what I spend on shop electric, but at $15 extra a month for the service, I would need a roughly $100 electric bill each month to make the tax deduction worth it. Not sure if I will have that or not as I've been on a shared meter so far and don't have much to go off.

Andy

[Gary Kvasnicka]

I buried 10/3 and installed a 30 amp subpanel 5 or 6 years ago. I wish I had spent the money for 60 or more amps, or at least buried conduit so I would not have to dig again. Never tripped a breaker, but when the DC is running (15A\120V) and I start any other motor the lights dim for a second until the motor is up to speed. I know I need to run bigger wire, just not looking forward to digging up the yard again. Besides my cheap labor has moved out of town. (son graduated college) Looks like I will have to hire a guy. :)

[zayd alle]

Chuck,

I'm currently wrapping up the same project. The previous owner did a horrendous wiring job in my detached garage -- so bad that I had to rip it all out and redo everything. After finishing the garage side of things (100A subpanel, 4 110v circuits and 2 220V circuits -- and don't forget the ground rod), I'm tackling the feed from the house. I can only go up to a 50A feed (100A main panel), so 6/3 wire will be the choice. The previous owner didn't have the foresight to run conduit, so I'll be digging a trench this weekend. Run a larger size conduit than is required and run some extra stuff while you're at it: an extra 12/2 Romex for a house-switched light at the garage, a phone line, and maybe even a CAT5 data cable.

Do it right and have peace of mind :)

Zayd

[Rob Russell]

Chuck,

I'm currently wrapping up the same project. The previous owner did a horrendous wiring job in my detached garage -- so bad that I had to rip it all out and redo everything. After finishing the garage side of things (100A subpanel, 4 110v circuits and 2 220V circuits -- and don't forget the ground rod), I'm tackling the feed from the house. I can only go up to a 50A feed (100A main panel), so 6/3 wire will be the choice. The previous owner didn't have the foresight to run conduit, so I'll be digging a trench this weekend. Run a larger size conduit than is required and run some extra stuff while you're at it: an extra 12/2 Romex for a house-switched light at the garage, a phone line, and maybe even a CAT5 data cable.

Do it right and have peace of mind :)

Zayd

Zayd,

NM Cable ("Romex" is one brand) is not rated for any use underground, whether in conduit or not. Underground is considered a "wet location" and NM isn't rated for that.

You're best off pulling individual conductors through the conduit. You can run #6 for the 50A subpanel and #12 for a 20A circuit for the light. Derating from bundling applies here, but as long as you're only going to make the subpanel 50A, you're OK. #6 THHN/THWN is rated for 65A so normally you could run a 60A subpanel with #6, but the derating limits you to 50A.

If you want to run low voltage, make your trench wide enough so you can have 12" between the line and low voltage runs of conduit. If for no other reason, you don't want the line level wiring to affect the phone/network cabling.

Rob

[zayd alle]

Zayd,

NM Cable ("Romex" is one brand) is not rated for any use underground, whether in conduit or not. Underground is considered a "wet location" and NM isn't rated for that.

You're best off pulling individual conductors through the conduit. You can run #6 for the 50A subpanel and #12 for a 20A circuit for the light. Derating from bundling applies here, but as long as you're only going to make the subpanel 50A, you're OK. #6 THHN/THWN is rated for 65A so normally you could run a 60A subpanel with #6, but the derating limits you to 50A.

If you want to run low voltage, make your trench wide enough so you can have 12" between the line and low voltage runs of conduit. If for no other reason, you don't want the line level wiring to affect the phone/network cabling.

Rob


Rob,

Thanks for cleaning up my answer. I don't usually get that lax with my details... :)

If the wire is in sealed conduit, is NM still unacceptable?

Zayd

[David G Baker]

Even if moisture can't get onto your sealed conduit you are not allowed to use it underground according to code. As Rod wrote "Underground is considered a "wet location" and NM isn't rated for that."
I have found it to be so much easier to run single wires in conduit. They move so much easier without the exterior coat that NM has. It gets difficult if you have to pull 4 larger wires at once but it can be done. I haven't read all of the posts, is there any reason why you can't use direct burial wire? If you dig a trench deep enough you don't have to worry about it getting damaged under normal conditions.

[David Dalzell]

:)The electricians just finished rewiring my garage/shop, about one hour ago. They put in an 80amp subpanel. It has 3 separate 240 volt circuits for a bandsaw (20 amp), tablesaw (20amp) and a jointer/planer (30amp). Aslo has two independent 120 volt circuits (20amp) for miscellaneous tools such as drill press, router, dust collector etc. I am a one man hobby shop so I will only be runing one major tool plus dust collector at a time. I have the bandsaw (just purchased), router and drill press. Now with all this electricity available I can justify buying the tablesaw, planner/jointer combo, and dust collector. I had everything done by an electrical contractor so I could be sure it was to code. Plus this all seemed beyond my abilities and comfort zone. The total cost was $1140, but this is California. By the way, I also put in four overhead dual lamp flourcent fixtures so I could see what I am working on. This I did myself. Now, to get the machines!