100A service, do I really need it?

[plmczy]

I have a small 20x25 2 car garage that has I believe 60 amp service in it already. I'd like to update the garage to 100 amp service sometime in the near future. I talked to my uncle who is a liscenced electrician and he told me that I really wouldn't need that much. I'm wondering is he right or would I benifit from having that much. I'm not really going to have alot of stuff. I want to get a bigger(ie stand up) air compressor, 187 hobart welder, blasting cabinet and have enough outlets for other things around the garage, oh yeah possibly a heater for the garage. What are some suggestions you guy's might have. Thanks for the help. later shawn

 

[ddawg16]

It's not so much that you would use 100 amps at any given time....but...there might be one time when you need the power....heater is going....you are using the welder and the compressor kicks on......

A 100A box cost almost nothing...and has more breaker slots. I don't ever really stress a ckt to it's limit...but I like having a lot of breakers so I can isolate areas more easily...and when you have a problem, it makes it easier to chase it down.

 

[bmwpower]

I listened to an electrician when I initially had them run 60A to my garage during the house build. After doing calculations, it turned out I was going to need 100A for all the stuff I wanted. Acutally probably could have used more, but the feed came from the house and the house is only 200A and maxed out as it is.

I ended up ripping out the conduit (too small) and putting in 100A. I ripped it out during the garage construction, so other than a ton of digging (electrician laid conduit BEFORE grading) and bigger conduit, it wasn't that bad.

If you want to do it the right way, see how much power you ned by doing a demand load calc. More here:

http://www.selfhelpforums.com/showthread.php?t=2011

 

[kbs2244]

Like goverment, our electrical needs only get bigger.
Go 100.
It dosn't cost that much more up front and saves a lot of time and trouble later.
That is why the power cos are only installing 200 now.
Most homes don't need it, but they will.

 

[timgr]

JMO - if you go with electric heat, you need at least a 100A service. Plus with a blast cabinet, you'll want a good sized compressor. Compressor plus heat is close to 60A. It would likely be ok, but your reserve capacity would be low.

 

[JohnK007]

It'll be cheaper in the long run to go 100A now rather than later. You never know what new "toys" you may add in the future that you're not thinking about now. Lift? Plasma cutter? etc.

 

[fotoflojoe]

I have a small 20x25 2 car garage that has I believe 60 amp service in it already. I'd like to update the garage to 100 amp service sometime in the near future. I talked to my uncle who is a liscenced electrician and he told me that I really wouldn't need that much. I'm wondering is he right or would I benifit from having that much. I'm not really going to have alot of stuff. I want to get a bigger(ie stand up) air compressor, 187 hobart welder, blasting cabinet and have enough outlets for other things around the garage, oh yeah possibly a heater for the garage. What are some suggestions you guy's might have. Thanks for the help. later shawn

Go with 100 amp. At some point, you'll be glad you did.

I was in the very same situation as you. I have almost exactly the same size garage. My FIL is a licensed electrician, when I told him that I wanted a 100 panel he also said that it would be overkill. Then, I laid out exactly what I had planned; plenty of outlets, more lighting, a large compressor, a welder, a heater (electric). Once he heard this, he said "Ok, I guess you do need a 100 amp panel."

Make sure your uncle understands exactly what you have planned for the future. Most people will think 100 amp is overkill, but then, most people won't be using their garages in the same manner that people on this board do.

 

[tfi racing]

If you were starting a new shop or if the existing service is unsafe or improperly installed,I would recommend 100 amps,chances are you will need to dig a new trench and run new conduit and wire.If your 60A is in good condition and you have adequate breaker space for your equipment,save your money and time,you will have to stuff a ton of equipment and have a few guys working full time in there to ever have a problem.Not many shops need more than 30A unless there is a large electrical heating or AC load.

 

[plmczy]

Thanks guy's. Actually my garage has no ceiling highth for a lift so that is something I don't have to worry about. I still have the glass fuses so that is a concern for me. Do I have to bury the line coming into the garage? Right now it runs from the corner of the house to an outside light pole then to the garage. later shawn

 

[nadogail]

I have found that Man Caves, or garage workshops seldom remain static. A prudent choice would be to never accept todays minimum standard. Allow room for improvement.

You most probably aquire another consumer of power (never allow anyone toy call them toys) to make your work better, easier, quicker or noisier.

The NEC (National Electric Code) is only the minimum standard. The NEC, when I taught Electrical Wiring several years ago mandated the minimum electrical service was 100 Amps, even to a studio apartment.

Also do not buy 14 guage wire, for the same reasons.

 

[Aceman]

Also do not buy 14 guage wire, for the same reasons.

Are you saying you personally don't buy #14 or that everyone else shouldn't?

 

[nissan_crawler]

Also do not buy 14 guage wire, for the same reasons.

I'll argue that, to a certain point. For wiring outlets, I agree. For running lights, I see no reason not to use it. I got a 1000' spool of 14-2-ground for $20. Every light in my house will be wired with it. I don't need more than a 15 amp breaker to run lights in couple of rooms, anyway.

As for 100 amp service, I would get it just for the breaker slots if nothing else, especially if you have fuses now. Although I will never pull 100 amps, I will have almost all the breaker slots used. I like dedicated breakers for things. Air compressor, plasma cutter, welder, drill press, table saw, all have their own breaker. If the SHTF, I want to be able to kill whatever it is without getting near it, and I don't want to be unscrewing a fuse. Each 3' strip, or 2 gang box (4 outlet) are on their own breaker. No worries of running halogen lights, and a chopsaw and killing half the power in the place.

I used the drill press one last week when I was drilling a thin piece of brittle metal (had it in a vise) that cracked, and started flinging around on the bit. I ran like hell, and went to the breaker box and killed it there. No way in hell I wanted to sit in front of that drill press and shut it off, even at low rpm.

 

[TheEquineFencer]

Here's my .02 worth, juts drop another service right at the building. I put in a 200A at my shop, not much more than a 100A. The building inspector asked "what the H__L are planning to run?" I told him anything I want. I had to put in a circuit for one GFCI receptical, one light in the shop and seperate GFCI circuits for the bathroom. After the inspection I could wire anything I wanted. I have 240VAC 17.3 CFM@175 PSI compressor, two 250A Mig welders, a 300A stick welder, plasma cutter, BridgePort Mill and a 15 inch lathe. The Mill and lathe are run off a Seimens Micromaster VFD, it's fed in 1PH and comes out 3PH. I started out with a 6HP Craftsmans 33 gallon compressor, drill press and a 225A Lincoln buzz box. Trust me, plan for future exspansion. Lighting is run on 14-2 with no more than 30% load on any circuit, I ran 10-2 for the recepticles, I hate voltage drop.

 

[mmg440]

I see you already have the 60 amp service. That is quite a bit unless you plan to use electrical heat you are probably fine. I would hold off. I you were putting in a new service and the 60 was not yet in place I would say go with the 100 amp but you have 0 expense to keep what you have verses adding a 100 amp probbaly a all new run that you may or may not need.

Just my 2 cents

 

[plmczy]

one of the reasons why I wanted 100 amp service is when ever I was welding with my Hobart 125(which now does not work,transformer problem) the lights would dim in the house and that would alarm my wife. I don't know if this is not enough power problem or if there is a power drop going from the house to the garage. When my water pump kicks on in the house they dim some but I figure thats just normal. At my buddy's house he has 200 amp service and when he welds his lights dim a little. Thanks for the tips guy's. later shawn

 

[mmg440]

It sounds like your house service is the one that needs the upgrade first. If your house lights are dimming it is the service in the house that is not handling the extra load of your garage sub panel and it should be upgraded before more is pulled off into the garage. Your service may be coming into the house may be to small of wire or a undersized service transformer for you use. But think it's best to upstream before moving down.

 

[nadogail]

About my remarks "Do Not Buy 14 Guage Wire"

I have stopped using 14 Guage for receptacles. I will use 14 to add an additional light fixture on a 15 amp circuit.

I regret having used 14 for receptacle circuits during a recent remodel, we keep finding more stuff to plug in. 12 Guage would have added 33% more capacity.

Sign me "Smarter than I used to be"

 

[kvom]

In my build the code required me to run 12ga for shop 110V outlets. I put GFI on everything. 4 separate circuits.

Upstairs I used 14ga, also 4 separate circuits including one dedicated outlet just for home theatre use.

I put in 200a service even though I doubt I'll ever use that much. But with 8 220V circuits (2 AC, 2 welder, 2 RPC, 1 lift, 1 compressor) you never can tell.

I would definitely go 100a service as well for OP.

 

[bigdav160]

If you didn't mention electric heat, I'd say you have plenty. The heat will push you over the edge.

Beware, upgrading isn't as easy as just hanging a new box. Almost every case you have to upgrade the feeder lines. If you are currently sub-ed off the main service that means upgrade wiring from the garage to house and house to pole/transformer.

Where I live, the homeowner pays for all those upgrades. The utility will not.

 

[oldgoat]

When I built my 22 x 26 I had to put new service to the house in anyway. I brought in 200 amp service and split off a 100 for the garage and the house. I would go with a min of a 100 amp to the garage. I know when I turn on the woodworking tools you can here one slow down a little for a while. I do wish that I would have split up so more of the outlets along the wall. I did put all 12ga. wire in for everything except of course the 220 outlet. It costs a little more but it gives me more confidence that I won't be undersize later on. I'd always go bigger and heavier as much as possible for a garage if I have a choice.

 

[Gary S]

About my remarks "Do Not Buy 14 Guage Wire"

I have stopped using 14 Guage for receptacles. I will use 14 to add an additional light fixture on a 15 amp circuit.

I regret having used 14 for receptacle circuits during a recent remodel, we keep finding more stuff to plug in. 12 Guage would have added 33% more capacity.

I think we all agree with you on that. All my receptacle circuits are #12 and 20 amp. I won't do any less. All my lighting circuits get the #14 and 15 amp breakers.
Running #14 for receptacle circuits seems to me to be a waste of time because so many tools and appliances require the 20 amp circuit and everytime you plug into one with a larger tool or appliance, you drop the breaker.

 

[octavio3311]

I think we all agree with you on that. All my receptacle circuits are #12 and 20 amp. I won't do any less. All my lighting circuits get the #14 and 15 amp breakers.
Running #14 for receptacle circuits seems to me to be a waste of time because so many tools and appliances require the 20 amp circuit and everytime you plug into one with a larger tool or appliance, you drop the breaker.

12G (20A circuits) are required in kitchens, bathrooms and laundry rooms - anywhere where the amp draw will be greater. The kitchen is usually the only room where multiple devices will be used simaltaneously - it's often common for blenders, mixers and toasters to be all on - therefore the need for multiple 20A circuits. Refrigerators, dryers, dishwashers, microwaves, hot tubs, jacuzzi's all require dedicated circuits anyway. At least in my part of the country. As for the receptacles throughout the rest of the house - living rooms, bedrooms, hallways, office, pantry, closets - why not run the 14G? What will be plugged into them - alarm clocks, maybe a table lamp, cordless phone, the largest load coming from a vacuum perhaps. 14G is fine for all that.

I do however recommend 12G in garages (you never know what you'll plug in out there) and dedicated lines to the home entertainment areas and the office computer area.

 

[moto.aero]

I did put all 12ga. wire in for everything except of course the 220 outlet.

what did you use for the 220? I assume it can be a smaller gauge because it's not pulling as many amps, right?

thanks

 

[JCByrd24]

I agree it sounds like your house needs upgrading before the shop; a new line/panel in the garage won't help the house lights dimming. If you shop panel has glass fuses and you want to upgrade the panel that can be done much more inexpensively than upgrading the actual service (new feeder wire, possible digging). You can install a 100A panel now for updated/more breakers. Keep the 60A breaker/fuse at the main panel and you're all set. I found that 60A would be fine in all but the worst cases (without electric heat/AC). Lights, compressor, welder running full bore, and a decent power tool running at the same time would be required to trip it, not a likely situation in my shop.

 

[nadogail]

Beware of 14 Guage wire and 15 Amp receptacle circuits. My 1988 built house met the NEC at the time. When I asked the builders electrical sub contractor "How much extra would it cost me for a 200 amp service? The sub repied "I don't do 200 Amp services" All the bathrooms were wired by the builder's with 15 Amp circuits. My wifes hairdryer draws 12.5 anmps.

I added a new circuit for the hairdryer, you can see the conduit on the side of the house.