How many circuits should I include in a sub-panel for workshop?

Question

I am looking to run a sub panel for a basement workshop approx 60 feet from the main panel, all inside. I have a table saw, jointer, band saw, planer, and dust vacuum, as well as routers and such. I was going to run a 60 amp breaker to a 100 amp sub with 6/3 cable. I wanted to run a higher breaker but then I am getting into much more money in the wiring.

My table saw draws 13 amps, and the planer draws 15. At some point down the road I plan on upgrading to larger tools, but for now they are more consumer grade.

In the panel I can run 3 20 amp breakers... lighting is actually run on another panel. Will 2 circuits be enough, or should I do 3? Any other ideas and recommendations are greatly appreciated!

Answer 1

This may not be worth the extra expense and work of installing a sub panel. Looking up some prices from the blue hardware store:

6/3 roll 50 ft       $102        12/2 roll 250 ft   $48
subpanel              $60        3 breakers         $20
3 subpanel breakers   $20        boxes and outlets  $25
main panel breaker    $20
12/2 roll 50 ft       $25
boxes and outlets     $25
-------------------------        ----------------------
total                $255        total              $93

I think 3 circuits is appropriate. One for the tool you're actively running, one for dust collection, and a spare if you need to be running two tools at once.

Edit: If you plan on upgrading to tools that will draw more than 20 amps, it may be worth the extra expense of putting in a subpanel. That way you can use shorter runs of 10/2 or 10/3 from the subpanel to the tools, instead of running all the way back to the main panel.

Answer 2

Not that it's a bigger deal later as compared to now, but why be bothered again later & have now's money go completely wasted. When you know you want to go to bigger draws in the future? Allegedly (I don't know this to be true), the Utility offers a discounted rate to 3-phase customers (consult your Utility).

If you're current 13A & 15A at 120V will be turning into double the Amps or up to whatever Amps at 240V then why not wire & plan the future layout now so you just need to deal with wire ends later on.

I just think you're jumping the gun right now & should reassess squeezing everything you can out of the current system, which likely won't be able to handle the future & may only handle the now.