Wiring Question

[Matt Benton]

I just moved, and need a little advice on setting up my new shop. I have a detached 2 car garage. It has a subpanel with (1) 30 amp and (5) 20 amp breakers. The garage only has 3 single-bulb lights and maybe 6 or 7 110 outlets, as well as a garage door opener. I haven't determined which lights/outlets run off of which circuits, but I'm sure the building isn't using anywhere near that much juice.

I need to wire a 3 HP DC and 3 HP planer (both 220 single phase). Can both of these tools run off of a single 50 amp circuit, or should I use separate 30 amp circuits for each tool? Also, would 12 gauge wire be appropriate? The panel is about 15-20 feet from where the tools will be....

Thanks!

[Dan Friedrichs]

Run 2 30a breakers, using 10ga wire. Technically you might be able to use 12 in some situations, but the cost is so minimal you might as well go a little oversize.

[Prashun Patel]

I agree with Dan: 2 separate circuits. However, I will say that when I was wiring for my saw, two different electricians advised me to run 12ga + 20A breakers. It's a balance; you want the breakers to trip if they have to, but not everytime you take a piece of 3" walnut to yr saw.

To complicate, you CAN run 10ga + 20A breakers, which would give you the protection but would save you the rewiring effort if you ever need more cowbell.

[Matt Benton]

Thanks for the replies, guys!

One other thing, the DC is an older cast aluminum, and the impeller is pretty heavy. Do you think 30 amp on the DC would be beneficial due to the load at startup?

[Prashun Patel]

Thanks for the replies, guys!

One other thing, the DC is an older cast aluminum, and the impeller is pretty heavy. Do you think 30 amp on the DC would be beneficial due to the load at startup?

Sorry for the cop-out here, but what do the specs say? It's guessing to do to otherwise.

[Logan William]

The motor on the DC should have a name plate that identifies how many Amps it will take, that is what you need to make sure you take into account.

[Chris Friesen]

Run 2 30a breakers, using 10ga wire. Technically you might be able to use 12 in some situations, but the cost is so minimal you might as well go a little oversize.

Might be worth checking the price. When I was wiring my shop, a roll of #10 cost about 75% more than a roll of #12. Also, #10 is much stiffer and harder to stuff into a box.

Typically 3HP motors will run just fine on 20A circuits. Certainly I haven't had any problem with my saw or planer. Normal breakers are designed to handle a certain amount of inrush current.

[Keith Blaszak]

Well I was going to chime in but it looks like the nail was hit right on the head here. I have a detached 2 car garage myself and I made these same electrical updates. I have a 3HP dust collecter a jointer & Bandsaw that I installed last year. Since I'm a hobbiest wood worker I ran the one dedicated
line for the DC and a second line for the Jointer/Bandsaw (under the idea that I would never be using both the jointer and bandsaw at the same time).

Well I guess I did chime in after all, anyways good luck!

[Matt Benton]

Thanks for all of the replies! F.L. Amps for the motor (I'm assuming that's fully loaded amps) are 14, so looks like I am going with 20 amp circuits and #12....

Thanks again!