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Should I upgrade to 20amps in my home garage workshop with several power tools?

Should I upgrade to 20amps in my home garage workshop with several power tools?

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  #1  
Old 07-19-11, 01:58 PM
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Should I upgrade to 20amps in my home garage workshop with several power tools?

I have a 15 amp, GFI protected circuit in my garage workshop with several power tools (table saw, miter saw, band saw, router, etc.). Is a current 15 amp circuit enough to run everything safely (not everything will be used at once) or should I upgrade to a 20 amp circuit with breaker, 12/2 wiring, receptacles. Also, I plan to use this circuit for outside Christmas lights too. My house is 18 years old.

Any advice on this is appreciated.
Thanks.
 
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  #2  
Old 07-19-11, 02:09 PM
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Attached or Detached garage? (Assuming attached) I'd say use the 15a for lighting and outside receptacle and a minimum of one new 20a circuit for garage receptacles. (Assuming detached) A 30 amp subpanel.
 
  #3  
Old 07-19-11, 02:13 PM
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The more amps, the better. That said, how will you get the new 12 ga wire to the shed?
 
  #4  
Old 07-19-11, 02:18 PM
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It's an attached garage. One other detail, I don't have any exterior receptacles in the front of my house and plan to add one or two to the 15amp circuit to power the xmas lighting.
 
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Old 07-19-11, 02:24 PM
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What type of and how many lights do you plan on putting up?
 
  #6  
Old 07-19-11, 02:42 PM
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Planning on putting up the standard LED icicle and tree lights.
 
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Old 07-19-11, 03:00 PM
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I use similar tools to you and I have two 20A circuits for receptacles plus one 15A circuit for indoor and outdoor lighting. This allows me to run a small window air conditioner and a shopvac for dust collection on one circuit and the power tool on the other circuit.

As long as you're pulling cables it's not that much more difficult or expensive to pull two or three than one so go big or go home. If you plan any major tool upgrades (cabinet saw, fixed dust collector, anything with 3hp or larger motor) then you may want to consider installing a conduit so you can pull wires for a 240V subpanel when you need it in the future.
 
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Old 07-19-11, 04:04 PM
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Planning on putting up the standard LED icicle and tree lights.
Then 15A is plenty. For the tools, I would pull a 20A MWBC. All receptacles need GFCI protection.
 
  #9  
Old 07-19-11, 04:17 PM
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Why would a GFI be needed for each receptacle? I thought only one was needed for each circuit?
 

Last edited by kevinf.; 07-19-11 at 04:32 PM.
  #10  
Old 07-19-11, 05:32 PM
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Originally Posted by kevinf. View Post
Why would a GFI be needed for each receptacle? I thought only one was needed for each circuit?
It's a wording thing. He wrote you need protection not an actual GFCI receptacle. If all the downstream are on the load side only the first needs to be a GFCI receptacle.

But then too he was writing about a multi-wire branch circuit and if you didn't split it at the first box you would need a GFCI receptacle at each box.
 
  #11  
Old 07-19-11, 10:50 PM
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Thanks everyone for all the advice.
 
  #12  
Old 07-23-11, 11:03 AM
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the chances at cutting wood during christmas is nill.. your good if not it will trip as designed then you know your limits..remember its the wires within the walls that the breaker protects not the load....i have 8-100 bulb light treee i spread from my peek during the holidays put an amp probe on it 5 amps tops just fuse the lights for christmas you'll be good to go
 
  #13  
Old 07-23-11, 06:53 PM
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i have 8-100 bulb light treee i spread from my peek during the holidays put an amp probe on it 5 amps tops just fuse the lights for christmas you'll be good to go
Unless you're using commercial light strings, you should have no more than three strings connected end-to-end. What it sounds like you are doing is extremely dangerous as the wires on consumer christmas tree lights are only good for three amps. Any more and they overheat.:NO NO NO:
 
  #14  
Old 07-23-11, 07:35 PM
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That's why they have fuse plugs with 3A fuses in them. It's impossible to overload them string to string. The extension cords and cube tap 'trees' most people use Clark Griswold style is a whole other issue.
 
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Old 07-23-11, 08:55 PM
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That's why they have fuse plugs with 3A fuses in them. It's impossible to overload them string to string.
I thought he was saying to put a 5A fuse in.
5 amps tops just fuse the lights for christmas you'll be good to go
They do manufacture lights with a 5A fuse if you want to pay for it, and the wires are real heavy.
 
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