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(Location: Ontario Canada if that makes a difference)

I want to run a 230V 1 PHASE 9.6 AMP table saw. I only have a single 15amp breaker that is not being used left in my panel.

To run the saw, is it enough to replace the 15amp breaker with a single-pole 20amp breaker and wire a new outlet into it (realizing the wiring needs to be compatible with 20amps)? Or do I need a double pole breaker?

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AFAIK, Canada uses the same split-phase arrangement as the USA to deliver 230 V to the premises, with the center tap grounded as the "neutral" wire.

So yes, you definitely need a double-pole breaker. Both "hot" wires need to be protected from over current.

  • Canada definitely has the same situation as the US here FYI. Two buses, 120v each with common neutral (grounded). – stevieb Jun 26 '18 at 16:58
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In North America where you are (thanks for clarifying by the way), you cannot get 240V from a single pole breaker. You need a 2 pole breaker, each pole connected to one of the two bus bars in the CB panel (there is a reason for that stipulation).

Your choices are to have an electrician see if it is possible to consolidate a couple of circuits in order to free up another space so that he can install a 2 pole breaker for your saw, buy a 120V motor for the saw, or install a transformer near the table saw that will take 120V in and give you 240V out. None of those options is going to be inexpensive, but I would opt for calling an electrician.

  • As a last resort, you could have a second panel installed as well. – Paul Belanger Jul 11 '18 at 3:10
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No. You need to deal with the overstuffed panel somehow.

And by "you" I mean either an electrician... or you after tossing away your electronic-design mindset, thoroughly digesting a book on home electrical, and asking some questions here on the DIY stack. You can't google knowledge like that, google only answers questions and you need a well rounded primer on the subject to even know which questions to ask.

Assuming we get past the initial formalities like dangerous FPE or Zinsco brands, dodgy Challengers and odd-layout hard-to-procure Pushmatics, and you have a workable panel... Then we can have a conversation about the service you have, how to rearrange what you have to get the spaces you need, whether you should be doing a subpanel, and how to provision the breaker you need.

By the way, this problem is typical of "Craigslist finds" - the reason the thing was cheap on Craigslist is the other fella was having trouble powering it too and never even ran it to test. Craigslist is glutted with 3-phase tools for that reason.

However given the power hunger of this saw, 240V single-phase (it is single-phase? Right?) is the right type of power to use. 9.6 amp is well within the working range of a 240V@15A circuit, cake for a 240V/20A circuit. But even if it could be jumpered for 120V, it would be 19.2A which is really kissing the limits for a 20A circuit. Got a 30A circuit anywhere? Dryer? (If so let's talk about that one, dryer circuits can be weirdly lethal.)

  • Thanks. Just gathering info to get estimates from professionals. – AfterWorkGuinness Jun 26 '18 at 17:31

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