De-rating 3 phase inverters - final result

Charles Ping · 2007-11-17T18:49:48+00:00

I've now got this sorted.I now have a single phase 240-415 transformer feeding a 10HP 3phase415volt inverter (the extra input is just linked in). It's *only just*happy starting the 3HP motor on my CVA lathe in top speed (2200rpm)but it works. The CVA gearing on a cold day is probably amongst themost extreme loading that you could engineer so I'm satisfied. Howeverit did take a quite a bit of faffing about with parameters to get itrunning OK.For any latecomers wondering why the hell I did this I found thatusing a Transwave converter on the 20amp garage circuit the start uploading on the lathe in top gear was just too high. I got bored ofreplacing fuses in an attempt to start the lathe. I'm effectively justusing the inverter to "manage" the current demand on start up.If anyone is curious as to why I didn't wire the lathe motor in deltaand use a single phase to 3 phase inverter it's down to cost. In 3HPform they are bloody expensive (£450+) and this second hand 10HPinverter cost a mere £27REgardsCharles