220 vs. 110v SWG

[tonyl]

I think you will find that all of them are 220v since most use 220v to power their pool pumps (lots cheaper). But also, most SWGs, give you the option to rewire via jumpers at a terminal on the SWG to convert to 110v

Don's right about most people using 220V but actually, it's not cheaper.
P(watts) = E(voltage)X I (amps). By doubling the voltage the amperage draw is halved, but the watts will be constant whether 220 or 110.

The cost is the same.