Originally Posted by

**Rob Stokes, N. Vancouver**
Nope, not quite like that. Power is measured in Watts. When you buy power from the power store, you buy it in Watts (kilowatts actually) with a time function attached (100 watts used for an hour is 1Kw/H). My power recently went to $0.063 per kW/h btw, but that's another story... A Watt is basically the voltage multiplied by the current. There's other parameters that go into it as well (power factors, motor effiiciency etc.) , but we can ignore those for now.

Let's look at the saw and for the purposes of discussion, let's assume it's a 1.5HP motor and let's also assume we live in a perfect world. While we're at it, I know that 1 HP = 746 Watts , but let's make it 750 for nice round numbers.

So, if 1HP is 750 wats, 1.5HP is 1125 Watts. If we assume your household voltage is 110VAC, and because Watts is volts times Amps, we can divide the Watts by the Volts to get the current draw (in Amps). 1125Watts/110VAC = 10.22 Amps.

So, if your saw is wired to 110VAC, it's going to draw 10.25 Amps..

But if we double the voltage and the Watts stays the same (which it will), you now have 1/2 the current draw or 5.11 Amps.

So, if your saw is wired to 220VAC, it's going to draw 5.1 Amps

Amps is current and current is work. More work, more heat. More current, more heat. cut the current in half, you cut the heat down. Motors don't like heat so a cooler motor will run longer..

BUT - a motor wired to 220VAC will give you no more power or output than a motor wired to 110VAC. And a motor wired to 220VAC will cost exactly the same as a motor run on 110VAC.

A motor wired to 220VAC may start faster than the same motor wired to 110VAC - but that's if you use the same wires to feed power to the saw. In that cse, the wires don't have to deleiver as much current at start-up and subsequentlly don't function as a choke.

Clear as mud? But with that all said, if it's possible to run a motor on higher voltage, you should because there's less current draw, there's less heat and it's a lot easier on your household wiring. But you get no more power and you won't save a nickle doing it.

AND- it's way cooler when the guys are borrowing your workbench for a beer holder to point at the "new" radial arm saw and saw "see that (sniff...) - that there saw's runnin' two-twenty!".

Rob