240V 20A, or 30A, or something else? e.g., air compressor, light duty welding

[steve in nj]

Hi, I'm a lurker here, but I'm building a new home and 3 car garage and the builder is finishing electrical wiring. I've asked for a 240V, 30A outlet, but that was a shot in the dark, not knowing what I'd use the outlet for and whether it was enough amperage or voltage for the sort of standard heavier duty garage tools that I haven't thought about in a while. Thank for any advice. This outlet would be serviced by a 300 Amp fuse panel located in the main home basement.

Steve

 

[royalton10]

Not sure whether your garage is a long wall from panel or if the garage will have drywall. With the 300 amp panel, I would consider having a 60 or 100 amp sub panel in the garage area to take care of what you want to have. You need to do some thinking about what you plan on having and future needs. The easiest time to get the wire there is during the building process.

Good luck and congratulations!!

 

[930dreamer]

I would have at least two 240v plugs in the garage. A 240v air compressor, welder and a hot water fired pressure washer etc. A plug near the big door in case you have something on a trailer. I use my 50 amp 240v circuit to power a rotary phase converter for 3 phase power machines. 930

 

[sberry]

Same here, sub panel where it was convenient or at least 2 240 circuits at a minimum. A 30 will cover light duty welding machines except for "buzz boxes" they require 50A which is considered a standard welder circuit. Some of the small migs are 30 or less.

 

[sams]

sorry for the off topic guys but I am curious about the power where there, so you all have the option of 110 or 220V power there? what voltage is 3 phase?

 

[BioHazard]

sorry for the off topic guys but I am curious about the power where there, so you all have the option of 110 or 220V power there? what voltage is 3 phase?

Normal residential power is two 120v legs, when combined give 240v. Most household circuits are 120v besides large things.

3 phase comes in various different kinds but one of the most common that I have at my shop is a 208v Y system, which gives 120v from hot to neutral, and 208v between any two hots. There is also a 120/240 3 phase system. (and more high voltage stuff)

 

[StumpFJ40]

Normal residential power is two 120v legs, when combined give 240v. Most household circuits are 120v besides large things.

3 phase comes in various different kinds but one of the most common that I have at my shop is a 208v Y system, which gives 120v from hot to neutral, and 208v between any two hots. There is also a 120/240 3 phase system. (and more high voltage stuff)

We're also 60hz... Basic residential power in Australia is 240/50hz.

 

[1Garageman]

I wonder how many nations besides us use the 120v? Is the 220+v more common around the world??? Just curious, and sorry to get of this topics main question.

 

[sams]

thanks biahazard, we have a simular thing in the rural areas of 240 + 240V, it's not heard of much though. The three phase here is 240/415V, are you sure yours isnt 110/190? I guess it's quite handy having that 220V available for equipment. The power cables you guys have to content with there must be really thick to allow for the higher currents. So hows the availablity of 220V gear?

StumpFJ40: I am familiar with that one, in that case it might be superior, as from my electrical theory the higher the frequency the less losses there are.

1Garageman: it wouldnt surprise me, I know china and atleast part of europe all use 220V, the UK is around there too. Also there is some talk in this area to go to 250V to get that little bit more out of the main supply cables without the maximum allowable voltage drop.

 

[bradleys]

steve in nj,

Are you putting your wire in conduit? If so, just have the electrician install conduit sized for 50 amps. Then, when you decide what you're going to run, you can pull the proper size wire. That's what I'm doing right now in my new garage. I'll have about a half dozen big boxes with conduit, but no wire or breakers yet. It's different if you're running the actual wires now, of course.

 

[Norcal]

thanks biahazard, we have a simular thing in the rural areas of 240 + 240V, it's not heard of much though. The three phase here is 240/415V, are you sure yours isnt 110/190? I guess it's quite handy having that 220V available for equipment. The power cables you guys have to content with there must be really thick to allow for the higher currents. So hows the availablity of 220V gear?

StumpFJ40: I am familiar with that one, in that case it might be superior, as from my electrical theory the higher the frequency the less losses there are.

1Garageman: it wouldnt surprise me, I know china and atleast part of europe all use 220V, the UK is around there too. Also there is some talk in this area to go to 250V to get that little bit more out of the main supply cables without the maximum allowable voltage drop.

In the US, standard residential voltage is 120/240 single phase, then there is 208Y/120V + there is 120/240V 3 phase, in larger commercial & industrial 480Y/277V is used, there are many referances to 110,220,440, & 550 volts but none of those exist anymore, those voltages ceased to be used in the 1st half of the last century.

 

[BioHazard]

The power cables you guys have to content with there must be really thick to allow for the higher currents. So hows the availablity of 220V gear?

Yeah, they can be, although 120v circuits are usually limited to 20 amps. Some dedicated things use more. Anything that uses more than that normally is 240v, like a dryer, stove, air compressor, welder, etc.

I believe the North American grid is the only place you find 120v, (Canada and Mexico too) part of Japan is only 100v....and most of the rest of the world is 220-240.

 

[sams]

oh ok, well thanks for the detailed answer guys, I found it most interesting

 

[steve in nj]

Thanks for the input. The electrician is going to install an outlet for 240V 20amps. If I need to upgrade I will run conduit on the garage wall from the panel in the basement. The basement panel is two separate panels at 190Amps each.

 

[1Garageman]

Check this picture out that chose the worlds electrical voltage. Found it on http://en.wikipedia.org/wiki/Mains_power_around_the_world

I thought it was fascinating, here is the main picture that shows the world.

 

[Steve from Socal]

If I were in your shoes I would ask the builder if they could run at least 3-4 conduit into the garage sized for say 60 amp service. If you have a compressor, welder, lift or, machines you will want more that one circuit. This is easiest and least expensive way to plan ahead.

I have a couple 60 amp, couple 40 amp and three 30 amp 240V circuits in the garage and I may need another two in the near future.

Steve