Running larger machines on single phase
Interested in your experiences running larger machines on single phase - and what you've found to be the practical limits in terms of HP or particular functionality.
Situation is this - no mains 3ph anywhere near my place, just LV 2ph on the pole. Currently have a 64A-1ph supply to the property, and good 32A supply to the shed.
Theoretically 32A is roughly 7.5kW (10HP), but I'm well aware that startup current etc can be LOTS higher depending on inertia and machine characteristics. Too much voltage drop from that can cause all sorts of control weirdness too, with contactors dropping out etc.
Soft starting using VFD's or using clutched machines that only spin up part of the machine on start can be used to reduce that start current requirement.
I'm looking at getting a slightly larger lathe, but they typically have 10 or 15hp motors. It would be a clutched spindle style.
My understanding is that as long as I don't need to use the full HP capability of the motor, (and can soft start the main motor) - that its possible to run a larger motor that what your supply can theoretically power.
ie I should be able to run a 15HP machine on my theoretical 10HP supply - but if I load it up and try and consume 12HP the supply won't cope and the main supply breaker will trip.
Is that basically correct, and if so - does it work in practice?
Anyone actually doing it?
Steve