I have a 5hp 230 single phase Leeson motor on my bandsaw. I ran a 30' circuit from a 30amp breaker in the panel to a NEMA 14-30 plug using 10AWG wire. From there, I have a 10-foot 10AWG cord to the saw. The connections are two loads and a ground, no neutral. Every time I turn on the bandsaw, the breaker pops immediately. I checked that the saw turned freely.
I had previously connected a dryer cord to it, also 10 feet long and 10AWG. The connection was two loads and a neutral. The saw ran fine. However, there was no blade so only the bottom wheel had to be turned. The dealer, Laguna, specifies that it is 30 amp. Any ideas how I can fix it?
Update
When I turn on the breaker, I can hear a solenoid clicking. When I turn the start switch, the blade starts to move before the breaker trips.
Plate on the motor
The 30 amp breaker
Update 2
I went back to the 10-30 cord and my 30amp dryer circuit. The connections are load, load, neutral as far as I can tell looking in the main panel. It works fine. It did take a few seconds to come up to speed. I put the 14-30 cord back on. The connections are load, load, ground. It still has the same problem. I tried the neutral on the new cord and got the same result.
I even read the manual. The spec for the LT18 bandsaw, which I have, is for a 30amp breaker. It also specifies that it has a 4.5hp motor so it may be out of date as it was written in 2008.
I did one more test. I hot wired the plug directly to the breaker in the panel using 10AWG wire I had left over. I got the same result. Could it be the breaker itself? I had previously used it for a 15amp motor and a 20amp, one at a time.
More images
The tripped 30amp breaker is for the bandsaw.
The circuit box at the bandsaw.
The wiring diagram from the manual. The image says LT16 HD. The manual is for the entire range of their Italian bandsaws.
This is the breaker for my dryer. This is one on which the bandsaw works. The wire from it looks like 10AWG at most.
Best Answer
NEC Table 430.245 states to size 5HP motor for 28A at 230V. Add 25% for start up and the circuit should be sized for 35 amps minimum. That would be #8 copper conductors with a 40A or 45A breaker.
The only way you could verify it is to check the amperage with an ammeter at start up and see if it is over 30A. That's probably is what is tripping your breaker.