soft starting single phase motor

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Revlac Guru Joined: 31/12/2016 Location: Australia Posts: 1267	Posted: 09:15am 19 Mar 2026       A changed the air compressor over too electric a month or 2 a go, it had a 8Hp ICE on it now 2Hp Electric motor 1400RPM and it has centrifugal start and 1 capacitor, with the start switch its 36A starting, when the switch failed and rotor locked I measured about 30A, the inverter in the shed starts this motor on the Air compressor quite well, even turned it off just before full pressure then back on again, it will pull a lot from the 48v battery banks, (a few old 4WD FLA batts and some old (secondhand) used and abused 200Ah LiFePO4) The other motor I might use for the block splitter is 2.2Kw 2900Rpm (capacitor start no centrifugal switch) but much easier to start, compared to the lower power motor on the compressor. Pete, Do you have a clamp meter with inrush measurement? It would be nice to find how much difference it makes using a soft starter, on the other hand if the motor starts and runs after putting in the soft starter, well that's good enough.   Quote   I did think that I may be able to use a drill and run the motor up to speed a bit then hit the start button. Yep done that a few times with some rewired 3phase motors. Edited 2026-03-19 19:23 by Revlac