Amps needed in workshop?

[RTcat]

RTcat is Online:
Join Date: Apr 2005
Location: South Central Wi
Posts: 1 Amps needed in new workshop

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I recently had a Cleary building (pole barn) put up and am trying to decide how to handle the electrical. Eventually I'll section off a part of the shed for a dedicated workshop. Basic items such as woodworking tools, air compressor, welder, table saw, etc along with lights will be the main use of the ele.

99% of the time it will just be me in the workshop enjoying quality garage time so only one tool will be in use at a time.

My two basic options are:

#1 Tap into the 200 amp service in the house and run a 100 amp out to the shed.

#2 Remove the 200 amp socket at the house and replace with a 300 amp socket and run 100 amp to the shed.

Ignoring the difference in cost of the above two options, is #2 overkill?

Basically I'm wondering how many amps the shed will draw. What kind of electrical set up do you guys with separate standing workshops have?

Thanks,
David

PS: Moderator, I was in the "barrel stove heat" thread and posted this by accident, thinking I was at the general page. Please remove this post from that thread.

 

[NSXSOON]

I have 100 amp sub panel in my 1400 square foot garage that is a tap off the house (3400 square feet) 200 amp main panel. for homeowner shops that are using say 1 or 2 high amp draw tools at any one time 100 amps is more than enough and won't effect the homes main service. If the operation of the garage is commercial in nature (2 or more people working with 4 or more machines on or starting at the same time) enlarging the main house panel would be wise.

Hope this helps.

 

[MXtras]

For most home shops, 100 amps is fine unless you have a large welder or are using electric heat.

With a big welder and a large air compressor, you can use 85 to 90 amps just for those two items alone. That doesn't leave much room for lighting, ventilation, etc.

What equipment do you plan to have in there?

Scott

 

[astroracer]

I ran 80 amps out to the sub-panel in my shop off the house 200 amp main panel. I have never had a problem while running the big welder along with the air compressor and a grinder all at the same time...
Mark

 

[MXtras]

My Synchrowave draws 96 amps at full tilt (which is rare but does happen) and my current POS, air compressor draws 25 at start-up. When welding Aluminum, if my compressor come on it trips the breaker and ruins the weld and the tungsten.

If you do not plan on having a large welder then 100 amps is likely more than adequate.

I would suggest that you should sit down and list the equipment you think you will have and the current requirements for each - this will dictate the size/capacity of your feed.

Don't forget to include lighting, ventilation, heat, stereo, computer.......what else?

Scott

 

[RTcat]

For most home shops, 100 amps is fine unless you have a large welder or are using electric heat.

With a big welder and a large air compressor, you can use 85 to 90 amps just for those two items alone. That doesn't leave much room for lighting, ventilation, etc.

What equipment do you plan to have in there?

Scott

Scott,

Just basic items as mentioned above; table saw, arc welder, grinder, 220 volt air compressor, hand power tools,

 

[mleichtle]

You'd have to do a load calc on the main dwelling to be absolutly certain. If you have wells, septic pumps, and alot of electrical appliances, you could be cutting it close "per code"

 

[MXtras]

What are you doing for heat?

I think you are going to be fine with 75-100 amps. It's cheaper to go big now than to replace later. When I ran 100A to my shop, I thought - fffftttt - I will never max this out. Now I wish I had 200 amps in the garage - but I get by with 100A.

Scott

 

[caffeine]

100 should be fun unless you like to turn on all your powertools at once........or you have some big welders, etc.

 

[TOMWELDS]

100amp should be fine. The houseload should be calc. If you have central a/c, elec range, etc. Run a 2" PVC conduit, incase down the road you get a synchrowave or larger welder. To go to a 300amp (which is 400amp equipment) service would be big bucks.

 

[krooser]

I've got 100 amp...never a problem...I've got welders, 5HP compressor, mill, belt sanders, disc sander...never even seen a load that could dim the lites...

 

[RTcat]

The electrictian stopped over last night, I'm going with option #1. Were going with 1/0 wire from the house to the shed. Down the road if I start running short on amps I can bring in 300 amp service at that time and pull off a 100 and send to the shed on the existing run.

Thanks for everyone's input. I'll post up some picks in the spring when we pour the floor.

 

[TOMWELDS]

You'll be fine. The last house i put 300amps in had 5 central a/c units, 210 high hats and was 10,000 sq. ft....LOL