40 Amp Circuit - What's the best utilization?

[Tim Dorcas]

I am getting ready to move to my new house and the garage is going to be where my shop is going to be. It is serviced by a 40 Amp circuit. I'm trying to figure out how to break this out.

1) Lights - Obviously I need to run lights. Not sure how many I can run on one circuit.

2) Air Filtration - Wondering if this could run on the same circuit at the lights?

3) Dust Collection - currently setup as 110 Volts (can't think of the amps at the moment). This is typically running whenever any other tool is running.

4) besides the things above I typically run one tool at a time. Tablesaw 110v, Lathe 220v, Drum Sander 110v, Planer 110v, Jointer 110v, ect.


I'm sure I'm not the only one that would have this setup. Any suggestions?

Thanks!

Tim

[George Bregar]

Run 40A to a panel. Run the required 120V and 240V circuits. You don't say how many amps any of your tools etc require. Impossible to advise without that. So do your homework, determine the amp requirements and come back.

[Scott T Smith]

Tim, if it were me I'd use the 40 amp circuit to feed a sub panel in the garage, and then run smaller circuits off of the new panel as needed for your equipment.

That way you can put the appropriate size breakers on your new circuits for the loads that they will carry.

[Dan Friedrichs]

Not really sure what your question is... I mean, when you install lights, you should determine how many you need, what their ampacity is, and from that, determine the size of their breaker. The only thing you need to know the main size for is to make sure your total load never exceeds that.

Are you perhaps thinking that because you only have 40A service, you only get 2, 20A breakers? Because that's not the case - you can have more

From your list, I'd suggest you wire the DC to 240V, as that is going to hog a lot of amps. Otherwise, your total load at any one time shouldn't be more than 40A, and you'll be fine.

EDIT: Sorry - I'm assuming the OP meant the 40A served a subpanel.

[Rod Sheridan]

Tim, as others have posted, use the 40A circuit to feed a panel in the new shop.

My shop has a 35A feeder which is more than adequate for my uses.

- 1.5HP cyclone

- most machines are 3 HP, one is 4 HP, all run from a 15A circuit.

The single 15A circuit for all the machines and portable tools is a multiwire branch, feeding 4" square boxes with a duplex 240V 15A receptacle and a duplex 15A 120 V receptacle.

Where required I have a GFCI receptacle installed.

Your 40A feeder may well be fine, what types of equipment are you planning on running?

Regards, Rod.

[Josiah Bartlett]

I run a 40amp subpanel in my garage shop. I have 1 15A circuit for the overhead fluorescent lights, 3 20 amp outlet circuits (one for each of the 3 walls), and one 30A/240V circuit with multiple outlets for the table saw, band saw, and air compressor. I never use more than one of those at a time. The only time I ever tripped the 40A breaker was when I had a ground wire touch one of the hot wires in a 240V 30A plug and it tripped both the 30A and 40A breaker at the same time.

[Rob Russell]

Tim,

Be aware that a "40 amp circuit" as currently wired may not be code-compliant for a subpanel. That circuit needs to have separate neutral and equipment grounding conductor feeds to properly supply a subpanel.

Rob