In article , Tom B wrote:
Flameproof suit on.

Laguna says 30 Amp breaker on 220 Volt service is needed for the
LT16HD (4.5 HP Baldor motor).

My quick calc shows 4.5 HP on 220V is ~3375 Watts or about 15.3 Amp.

That's assuming 100% efficiency, which you're not going to get. Figure
*at*least* 20A, probably more.

Is the start-up draw 30% higher than the run draw?

No, it's even worse than that.

I have 220V 20A service and 10-3 wiring installed over about a 20'
span and wonder if I need to go up to a 30 Amp breaker.

The manufacturer recommends a 30A circuit.
10-3 wire will support a 30A circuit.
A 30A double pole breaker will cost about ten bucks, and take you fifteen
minutes, tops, to swap in.

Doesn't sound like a difficult decision to me.

I could just plug it in, crank it up, and see if the breaker pops :-).

Yes, you could. Or you could spend the ten bucks and fifteen minutes, and
put in the correct breaker.

Your choice. :-)

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.