Single phase supply

[Justin91]

If I have a 240/480 volt dual voltage single phase motor connected by 2.5mm 2c+e to an isolator and then just 1mm flex coming out with active, neutral and earth connected is it possible the power supply to be 480v or is it most definitely 240v

 

[Justin91]

it was driving a fan not heavy at all for a ventilation system and yes I was sent there because it was not drawing the air it should, The connections where changed I believe and run with 240v and still had low torque then pulled apart by a motor rewind shop and apparently laminations are no good.

 

[ElectroChem]

I guess it's possible that it's been run on 400-415 by pinching two phases from the supply and running a dodgy install. That degree of undervolting would still not be good for the motor but less so than 1/2 rated supply.

Edit: Where are you based? I could possibly swing past one day after work to have a look at the motor if you're in western Sydney

 

[Justin91]

appreciate the offer but I’m in Newcastle might be a bit out of your way, and thanks for all the information i am learning more and more as I look into it. I’m going back to the site in a few days and will post how everything goes.

 

[Justin91]

old motors are connected for 480v supply but the supply was 240v and they have been running continuously for many years like that and I guess that’s why the old motors have damaged windings and lamination. New 240v motors are installed and all good.