3 phase motor wiring - Electricians Forum | Electrical Forum | An electrical forum for electricians in the UK

sean · 08-10-2007

Hi i have recently reconected a 3 phase fan at my workshop its rotation is correct but it now gets very hot any suggestions?

25-10-2007

Hi,
If the current on each of the three phases is uneven, the polarity of the windings may
be incorrect? ..or you may have connected the motor in the delta configuration instead
of star (6 terminals on motor?)

SCOL1 · 19-02-2008

Quote:

Originally Posted by Unregistered

Hi,
If the current on each of the three phases is uneven, the polarity of the windings may
be incorrect? ..or you may have connected the motor in the delta configuration instead
of star (6 terminals on motor?)

wouldn't this cause tripping on start-up ?

27-02-2008

Quote:

Originally Posted by SCOL1

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wouldn't this cause tripping on start-up ?

Depends on what starter you were using!!

What is the KW rating of the motor??

Has it got DOL, Star/delta, soft starter, invertor etc for starting?

Is it squirrel cage, wound rotor, reaction etc etc

Some more details would be nice, take a look on the rating plate if you are not sure

mattyfooty · 03-03-2008

I agree with what has been said already, sounds like motor is connected in delta. On a standard cage 400/230 3ph motor this means that 400v are across a 230 winding, on a small motor it will start up no problem in delta just it will over heat and eventually fail. Or you could be using a non standard winding like 380/200, really need more info from motor plate/start control.