100, or 200 amp service, to Garage

[mscher]

Plan to run 220V to 3 car detached garage, from 200 amp home service, about 65 feet or so, indirectly.

I'll be running fairly large garage air compressor, stick welder, lights, maybe electric heat and A/C. Garage door openers.

First off, do I even need 200 amp, or is there any advantage to spending the additional money?

Is there any ball park price between the two? What is the best wire to use?

Also, is it at all, unheard of, to have an electrician just do the hookup, while I do the drilling, running of wires and burial?

 

[dingbat]

Re: 100, or 200 amp service, to Garage

You cant use more than you have at the main. If you need 200 amp in the garage, you need to have a second, independent service run to the garage. Unless you plan to run everything at the same time, 100 amp should be more than enough.

Electrical code requirements for wire sizes etc. vary by location.

 

[rbh]

Re: 100, or 200 amp service, to Garage

Just add up what all could be running at the same time to make a decision.

Welder + compressor + battery charger + heat + lights, ETC+ ETC.

(Total load)

As well copper wire will out distance and out due aluminum wire, but at a big cost.

(100 amp service becomes a 50 amp service+-)

 

[bigdee]

Re: 100, or 200 amp service, to Garage

For most shops 100 amps is plenty. The only thing that might take you beyond that would be the amount (Kw) electric heat you choose to use. With the exception of the electric heat the compressor is the larger demand, welders under 200 amps do not put that much Kw demand on your service. If you can keep the heat under 10Kw you can probably get by with a 100 amps.

 

[KD4UPL]

Re: 100, or 200 amp service, to Garage

It will be difficult to impossible to find a 200A breaker to put into the panel in your house to feed that much to a garage. Most brands only offer up to a 125 amp breaker. Some make a 150 amp. Either way, it's an expensive breaker to buy.
100 amps should be enough for your shop if you don't carried away with the electric heat. In fact, if it were me, I would find another way to heat. Electric resistance heat is about the most expensive method available.
For 100 amps #2 aluminum is most commonly used. Some people will tell you all kinds of reasons not to use aluminum wire. 90% of more of the residential electrical services in this country use it. All overhead service wire is aluminum.
You could use URD or USE and direct bury the wire but I would use XHHW and put it in conduit.
I'm sure you could find an electrician to do the hookup if you look hard. Lots of people need work right now. I'm an electrical contractor and I never liked to work that way because of liability. If I do some work on a project and latter someone is killed or something burns down I could get sued. So, I liked to know for certain that I did everything right. If something goes wrong and there's two people involved (home owner and me) then blame gets pushed around and how do you know who did what?
I've also see d0-it-yourselfers over pay for substandard materials and take a really long time doing work I had to straighten out when I got there. They could probably have just hired me for the whole job and not spent any more money to have it done right.

 

[NewfieDan]

Re: 100, or 200 amp service, to Garage

My shop has a 70A service. I have electric heat, a small wire feed welder, a 15gal compressor, plus numerous large wood working tools. Never had a problem with it tripping. In addition I also have a large garage(no heat) and a huge gazebo with a 6 person hot tub fed off the same 70A service. The large garage has a 60A fed from the shop, the hot tub in the gazebo uses a 40A branch from the big garage.

I usually do a lot of woodworking so I have a some fairly large commercial sized tools. Still no issue. Before I moved from the west I had another shop. Also fed from a 60A service. In that shop I had incandescent bulbs(less efficient than fluorescent) a 7HP compressor (60gal) gas heat and the same welder. Also never had an issue with anything tripping.

Go with cooper feeds as RBI said. To get the same current you will have to upsize your conductors by at least one size. Do yourself a huge favour now. Put in 2 oversize conduits, one for power an the second for TV, phone etc. Trust me on this, it will likely turn into a guys hangout, always good to hangout watch the game, without bothering the Admiral.

If you put the conduits in and decide to change later it is much easier. You won't have to dig anything up to change.

Also consider lights on the outside of your shop. Will you ever want to turn the outside shop lights on/off from the house, especially during poor weather. Now is the time to consider this, or will motion lights work for you?

FIY I am an electrician with about 20yrs experience.

 

[Georgesalmon]

Re: 100, or 200 amp service, to Garage

I have a 200amp property service, its divided on a pole on the garage. 100amp to the house, 100amp to the garage. I have large compressor, welders, drill presses, lathe, other stuff. 100amp is fine but I don't have electric heat, I have a propane fired high efficiency furnace like in a house with duct work. I used AL wire cause of cost, if you do that remember to get that special goop for the ends and use it. Also tighten the clamps every week for a months, AL will crush and get loose. No problems for 6 years now.

 

[gm280]

Re: 100, or 200 amp service, to Garage

When I built my shop I knew going in that I was going to install a 200 amp service. But you absolutely positively can't tap off your home 200 amp panel and run to your shop. That IS against all electrical code most any place. I had the electric company run a 400 amp service to my house with separate shut-off switch panels (per code here and probably there too where you live) for each 200 amp service to the house and shop. So now my shop has its own 200 amp 220volt setup so I can use anything up to 200 amps at 220 volts if I need too. And the house still has its own 200 amp 220volt service as well. That IS the best way to do things like that. Go by the legal electrical code so your insurance won't be effected by any issues either. And the cost to do it this way (the legal way) was not nearly as much as you would expect. The power company paid the cost for the up-grade to the house. It is their service until I take over after their meter. So my cost was the two switch boxes and of course the 200 amp service panel in my shop.

 

[jc55]

Re: 100, or 200 amp service, to Garage

GM, surely you could run a 100 amp breaker to the shop as a sub panel couldn't you? In my situation, the electric company suggests a 320 amp service in my shop at home, then run a feed to the existing 200 amp service in the house. That way, nothing is changed in the home. I prefer 200 amp services for a shop, but even my dad runs 100 amp with a mill, a lathe, band saw, 80 gal compressor, and a stick welder. Not at the same time though

 

[bigdee]

Re: 100, or 200 amp service, to Garage

But you absolutely positively can't tap off your home 200 amp panel and run to your shop. That IS against all electrical code most any place.

Wrong! Unless stated differently by your local jurisdiction the NEC does NOT specify a maximum size limit for a subpanel. The over current protection is limited by the main breaker in the main panel so it would be impossible to overload the main. By the way the largest plug-in double pole breaker you can buy is 125 amps.

 

[gm280]

Re: 100, or 200 amp service, to Garage

bigdee, I know here in my area what the electrical code stated and I had to go the way I did by that code. I also got the required permits and had the county inspector inspect all my work to finalize all my shop wiring. Both the inspector and the power company stated that they have never seen such quality wiring in all their days. In fact the county inspector stated that I knew the code better then he did... That kind of scared me a little thinking he wasn't as up on the actual code as I was... But my insurance is intact for any problems because I had it all done properly and to current code. If you go your own way without permits and inspections, your insurance may not pay off in the event of some serious fire and/or damage to your shop OR maybe even your home... Just saying!

 

[bigdee]

Re: 100, or 200 amp service, to Garage

bigdee, I know here in my area what the electrical code stated and I had to go the way I did by that code. I also got the required permits and had the county inspector inspect all my work to finalize all my shop wiring. Both the inspector and the power company stated that they have never seen such quality wiring in all their days. In fact the county inspector stated that I knew the code better then he did... That kind of scared me a little thinking he wasn't as up on the actual code as I was... But my insurance is intact for any problems because I had it all done properly and to current code. If you go your own way without permits and inspections, your insurance may not pay off in the event of some serious fire and/or damage to your shop OR maybe even your home... Just saying!

Your local inspector may require that BUT the NEC does NOT. I was a licensed electrical contractor so I am well aware of code requirements. Insurance goes by the NEC which is underwritten by the National Fire Protection Agency. Local inspectors can make rules ABOVE code if they desire (or don't know better).

 

[jimbo_jwc]

Re: 100, or 200 amp service, to Garage

Code is suggested ,replaced enough direct burial where insulation got nicked somehow and festered , concure with copper and 4inch sch80 pvc as friends have stuffed everything from shop air to house gas line and now I'm considering running lines in my barn's sewer to house from woodburning water heater to FCE . I have 200A feed at Barn w/its own transformer and remote RF transmitting Meter after horse run out and scarred meter reader . Most around here use 60 amp to feed from house or 50 range breaker and handles their needs .

 

[bigdee]

Re: 100, or 200 amp service, to Garage

Code is suggested ,replaced enough direct burial where insulation got nicked somehow and festered , concure with copper and 4inch sch80 pvc as friends have stuffed everything from shop air to house gas line and now I'm considering running lines in my barn's sewer to house from woodburning water heater to FCE . I have 200A feed at Barn w/its own transformer and remote RF transmitting Meter after horse run out and scarred meter reader . Most around here use 60 amp to feed from house or 50 range breaker and handles their needs .

Aluminum direct burial tri-plex along with #6 ground is fine. Copper is a big waste of money for a service. Just bury it deep enough and layer sand over it if you have jagged rocks. The electric utility uses underground aluminum tri-plex without issue.
I have replaced more shorted underground conductors run in conduit than I have in direct burial.

 

[agallant80]

Re: 100, or 200 amp service, to Garage

I have 60A (2X30) running to my shop. I can run my 240V table saw, dust collector, compressor, battery charger for cordless tools, lights and radio at the same time.I have tripped a breaker in the shop before bogging down the drum sander (should have run a dedicated 20A for it) but I have never tripped the breaker of the feed pannel.

I would be more concerned about having several dedicated 20A outlets in the shop. That was my mistake, all of the wall outlets and lights run off of one 20A breaker and it will trip from time to time. 100A to the shop is more than enough.

 

[bigdee]

Re: 100, or 200 amp service, to Garage

I have 60A (2X30) running to my shop. I can run my 240V table saw, dust collector, compressor, battery charger for cordless tools, lights and radio at the same time.I have tripped a breaker in the shop before bogging down the drum sander (should have run a dedicated 20A for it) but I have never tripped the breaker of the feed pannel.

I would be more concerned about having several dedicated 20A outlets in the shop. That was my mistake, all of the wall outlets and lights run off of one 20A breaker and it will trip from time to time. 100A to the shop is more than enough.

Good point

 

[oldjeep]

Re: 100, or 200 amp service, to Garage

I've only got 40amps running to my shop (into a 60 amp fusebox), which has always been enough for a Hobart 180 welder, small fridge, tv and a lot of lights. You really have to work at using power to worry about 100amp service - or have multiple people operating multiple machines.

 

[jimbo_jwc]

Re: 100, or 200 amp service, to Garage

Replaced from heat shorted melted overloaded,or moisture festered shorted , to ground or nicked bad from fittings ?

Aluminum direct burial tri-plex along with #6 ground is fine. Copper is a big waste of money for a service. Just bury it deep enough and layer sand over it if you have jagged rocks. The electric utility uses underground aluminum tri-plex without issue.
I have replaced more shorted underground conductors run in conduit than I have in direct burial.

 

[jimbo_jwc]

Re: 100, or 200 amp service, to Garage

We sometimes dye the sand red or use yellow caution tape to stop intrusions , Conductors overhead in air can handle more current and less cost as can sometimes be smaller .

Aluminum direct burial tri-plex along with #6 ground is fine. Copper is a big waste of money for a service. Just bury it deep enough and layer sand over it if you have jagged rocks. The electric utility uses underground aluminum tri-plex without issue.
I have replaced more shorted underground conductors run in conduit than I have in direct burial.

 

[bigdee]

Re: 100, or 200 amp service, to Garage

Replaced from heat shorted melted overloaded,or moisture festered shorted , to ground or nicked bad from fittings ?

2 & 3 but the majority were a combination of age and moisture. In every case conduit had water in it. This was such a big issue at a Campbell Soup facility that we had to put drains in the conduits....never had a problem with the direct burial.