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Megga readings on a motor

I have just aquired an old geared head drill press. The motor has

wires so I have cut the star point off and paired them up in delta an conected to an Mitsubishi inverter i have inverter goes up to 50Hz an reads 230V on the output terminals but no movement from the motor.

Motor turns ok if quill turns so gears are engaged ok.

If I borrow the Megga from work what should the readings be fro winding to winding and winding to the casing.

Use 500 or 1000 Volts

Steve Larne

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Using my hand cranked megger; I would expect > 20MOhm for both. I would imagine this is < 500 V as it's an old bakelite cased Megger model.

Alan

Reply to
Alan Bain

When I borrow a megga it has nice instructions in the lid, and the dial has a green section on it for each test.

hth Dave

Reply to
dave sanderson

hi it sounds like you have a open delta if your motor wont run you have to mark the three wires from the star point A1/B1/C1 find the other end that was used as the input side of the 415v and mark these as A2/B2/C2 for star 415v you link a1,b1,c1 and put power on a2,b2,c2.for 220v you link a1 to c2/ b1 to a2/c1 to b2 and then you can run you inverter hope this helps kevin

Reply to
lecmotors

Thanks for making me think.

I had brought the star point out and cut the wires but connected eac coil to one phase of the output. Sorted now though. Really iratating as i have set them up as work in a old job 15 years ago no problem. Always had the benifit of 6 termina motors with links then.

Steve Larne

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