Question for Electrical Gurus

[txwhitetail]

Working on buying supplies to wire my shop.

On regular 2 gang boxes going to 20 amp breakers bow many gang boxes should I wire up per circuit?

I know depends on the load but these will mainly be for grinders, circular saws, etc.

My big drill press, bandsaw, etc will be on their own circuit.

I cant decide between 2 or 3 gang boxes per run. Reason I ask is I will have three on each side and one on the ends making 8 total. 2 each may make the most mathematical sense. Just trying to buy enough wire.

[hot_rod_eddie]

Of course depending on load and what you are planning to operate at the same time. You can put up to 8 or so per code. I put as many as necessary to go around the garage. Since you will be using higher amp tools, I would run two 20 amp circuits. For my 2 car garage 6 outlets was enough. One circuit for 2 outlets and lights, 4 outlets on the 2nd circuit.

[WTucker]

There is no code saying you can only put 8. The rule of thumb for residential work is 10 per 20 amp circuit and 8 per 15 amp circuit. In a shop, I would install depending on the load and how much you think you will use at the same time.

[WTucker]

You are doing right by running dedicated circuits to the big items, how many total receptacles do you plan to install?

[FLASH_OUTDOORS]

Question for Electrical Gurus

You are only 1 person. You should consider what will be running at the same time. If all the plugs are for “hand tools” you could use 1 20amp circuit for entire shop. (Technically)


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[txwhitetail]

You are doing right by running dedicated circuits to the big items, how many total receptacles do you plan to install?

I am planning 8 - 2 gang boxes so 16 receptacles. All of my heavier stuff will have dedicated circuit (welders, band saw, big drill press, etc).

This is a 24x30 shop I was thinking 3 - 2 gang boxes on each 30’ side and one on each end. (Doors are on one 24’ side.

I’m in Non-code area.

[Mike D]

WTucker is right, NEC says 180 Watts per receptacle. 10 on a 20A ckt is pretty much the accepted standard.

If you have a workbench where you may have multiple tools will be plugged in at the same time you may consider a plugmold strip instead of individual boxes.

Otherwise for dedicated tools use a single outlet with a 4 square box and raised industrial cover for the appropriate receptacle. This way you don’t have to put in a GFCI.

For any receptacle that you will be plugging anything into either use a GFCI breaker or GFCI receptacles. Use can still is 4 square boxes and raised industrial covers for these.


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[WTucker]

I am planning 8 - 2 gang boxes so 16 receptacles. All of my heavier stuff will have dedicated circuit (welders, band saw, big drill press, etc).

This is a 24x30 shop I was thinking 3 - 2 gang boxes on each 30’ side and one on each end. (Doors are on one 24’ side.

I’m in Non-code area.

I would run a circuit to each side, while catching one end with each circuit. So you would have 8 receptacles each. If you have somebody else working with you using tools at the same time, they can plug into the other circuit if you have issues.


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[txwhitetail]

WTucker is right, NEC says 180 Watts per receptacle. 10 on a 20A ckt is pretty much the accepted standard.

If you have a workbench where you may have multiple tools will be plugged in at the same time you may consider a plugmold strip instead of individual boxes.

Otherwise for dedicated tools use a single outlet with a 4 square box and raised industrial cover for the appropriate receptacle. This way you don’t have to put in a GFCI.

For any receptacle that you will be plugging anything into either use a GFCI breaker or GFCI receptacles. Use can still is 4 square boxes and raised industrial covers for these.


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Would the gfci breaker be the way to go? I know the gfci receptacles get a lot more expensive.

[WTucker]

Doing this, you will want either 2 GFCI breakers or 2 receptacles. The breakers are near $50 each. If you buy the receptacles, buy a commercial grade 20 amp GFCI. They have always been more robust in my experience.

[Gummi Bear]

Question for Electrical Gurus

Put a receptacle on either side of a roll up door. you'll be glad you did.

Also - for a shop, I think of anything I plug in to be of heavy use, when compared to what might be plugged in inside of a house.

Put 3 of those quad outlets on a circuit, that's what I did. I put receptacles every 8-10' all the way around the shop when I wired it up.

I also added extra receptacles at the work bench, and put a welder outlet near each overhead door.

Everything is in EMT and 4sq boxes. I oversized the homerun conduit, so I can pull an extra circuit if I ever need to.

You're on the right path with dedicated circuits for big equipment.

Spend the money now on commercial grade devices. Do not buy craptastic residential grade, they will fail.

Quality GFI device will run $13-$20 each.

[txwhitetail]

Doing this, you will want either 2 GFCI breakers or 2 receptacles. The breakers are near $50 each. If you buy the receptacles, buy a commercial grade 20 amp GFCI. They have always been more robust in my experience.

What should the receptacles run? I'm seeing $15-30+ each.

[WTucker]

For a high quality GFCI it may cost you $20-30. If you go with a cheap residential grade you will lose money the first time you have to replace it. You only need 2 of these.

[txwhitetail]

For a high quality GFCI it may cost you $20-30. If you go with a cheap residential grade you will lose money the first time you have to replace it. You only need 2 of these.

Ok so just one on each circuit. My DA was thinking I had to use on all.

[WTucker]

Yes, the first receptacle you hit on the circuit will be the GFCI. Your home run will connect to the “line” side. All other receptacles on the circuit will be fed and protected from the “load” side of the GFCI.