John,
Yeah, that's the question. I dunno!!
The motor is a 4 pole, ML90L4 at 1.5kW.
I can't find the data sheet for the exact motor (Dajin?, never heard of 'em) but this is close:
http://www.mikrospin.co.uk/downloads/108/1-phase-motors-technical-datasheet.ashx.
This gives the...