Most home shops run on one or two circuits originally installed for a garage door opener and a few outlets. This is adequate for a single cordless tool and a shop light. It is not adequate for a table saw, a dust collector, a planer, and a shop vac running simultaneously – or even sequentially if you haven’t thought carefully about circuit loading. The first time you trip the breaker mid-cut, you’ll begin thinking about an electrical upgrade. Do it before the trip, not after.
The minimum upgrade for a working shop: a dedicated 20-amp circuit for the table saw and another for the dust collector. These two machines draw the most current and need their own circuits. Running them on shared circuits with your lights, outlets, and other tools is how you end up with lights dimming every time you start the saw – and how you end up with a breaker trip at the worst possible moment.
Reader Tim, an electrician by trade, made the case for a more comprehensive shop electrical upgrade in a post that generated more discussion than almost anything we’ve published: a 60-amp subpanel in the shop, fed from the main panel, with dedicated circuits for every stationary machine. The upfront cost ($400-800 for the subpanel, branch breakers, and wiring, assuming you do the work yourself) pays for itself in convenience, safety, and the elimination of extension cords that run across the floor and under work areas.
His specific recommendation: plan for more circuits than you currently need. Installing the conduit and breakers for 12 circuits when you only need 6 right now costs almost nothing extra and saves a complete reinstall later. Future machines, a dedicated outlet for a charging station, a 240V receptacle for when you eventually buy that jointer – they all benefit from preplanned capacity. Tell us about your shop electrical setup – and the moment you knew you needed to upgrade it.