Spindle motor rewind

[johnsattuk]

Update

I have eventually rewound my 2 pole spindle to 8 pole, dragged on a bit for a variety of reasons. Did a little research on rotor slot numbers, seems to be a bit of a black art with different motor manufactures doing their own thing, seems to be more to do with starting torque and efficiencies than any thing else.

Invested in a winding design service on the net, asked for 240v 400Hz delta connection, came up with 20 turns per slot.

Wound the stator at 20 turns two in hand 0.75mm wire, ~20A in delta no load running - ~12A in star, this was about 8 times the original motor.

Some emails back and forth getting me nowhere, seemed obvious to me that it was lack of turns (flux).

Decided to think it through on the basis that I knew the turns and current of the original motor and that HSD had got the ampere turns right.

Fortunately I had tried the motor before varnishing it so I was able to strip it down again very easily.

Wound the stator at 50 turns two in hand 0.55 wire, ~2.5A in delta no load running similar to the original motor, runs OK up to 500Hz which is more than I want.

From when I was a young lad my Father repeatedly told me ' Beware the Expert'

Not particularly neat but does the job OK