Breaker size

[Sean Troy]

Hi all, I'm going to start wiring my shop tommorrow and was wondering what size breaker to run for my table saw. It's 3HP and the specs say 18amps and they recommend a 20 amp breaker. I'm assuming the 18 amps is under start up load but wouldn't that call for a 30 amp breaker? Thanks for any help. Sean

[Jim Becker]

Most 3hp table saws run fine on a 20 amp 240v circuit. There is no harm in putting in a 30 amp setup, however...

[glenn bradley]

The breaker protects the circuit, not the tool. As long as your wiring and outlet is spec'd for 30 amps, I would see no problem. If the components (outlets and such, not the tool) in your line are rated lower than your breaker you are defeating the breakers ability to protect the circuit. this doesn't mean don't do it. It just means make sure that everything between panel and outlet are rated correctly.

[Bruce Shiverdecker]

I agree with Glen.

If the wire is 12 guage, use a 20 Amp breaker

If 10 guage wire, use a 30 Amp breaker

Bruce

[Peter Stahl]

Wired my unisaw with 12 gauge wire/20 amp breaker and never a problem.

[Rick Christopherson]

Hi all, I'm going to start wiring my shop tommorrow and was wondering what size breaker to run for my table saw. It's 3HP and the specs say 18amps and they recommend a 20 amp breaker. I'm assuming the 18 amps is under start up load but wouldn't that call for a 30 amp breaker? Thanks for any help. SeanNo, the 18 amps is the full-load amperage, which is when you bog the machine down to the point where it no longer cuts productively. The startup current is much, much higher, and you do not size the circuit to the startup (inrush) current.

Your saw, however, rarely ever sees full-load amps, and spends the majority of its life just above idle to 75% of full load.

Your saw will operate correctly and safely from a 20 amp circuit with #12 wire. There is nothing wrong with using #10 and a 30-amp circuit, just so long as you understand that there is no net benefit either.You are not likely to sell your 3 hp saw and replace it with a 5 hp saw; nor are you likely to ever share this circuit with another heavy load.

[Sean Troy]

Thanks all, I think I'll go with the 12/20amp