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motors 1

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mjsl2

Electrical
Jan 11, 2007
3
how do you change a star delta wired motor to run on direct on line
 
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Connect the motor terminals (6 number) in delta and then use the O/L relay and main contactor (remove star and delta contactor and all interlocks)
 
whats the power of the motor ? if its too high you need to control the current cause it may high
 
its a submersible pump, dont realy want open the terminal box. there 6 wires +earth comming out of the pump.
 
Do not follow shreesathe's advice without checking your equipment out thoroughly!

The main contactor is usually NOT rated to carry the full load current, and the OL relay is typically set for 58% of FLA as well. Either buy a new contactor rated for the full current (preferable) or use the Main and Delta contactors in parallel, then replace the OL and place it in the circuit ahead of BOTH contactors so that it sees the FLA.

For some reason the thread number provided by aolalde is gone, but here is another one where he posted the connection pattern you will need. (second post in this thread). thread237-173798
But really, if you choose to continue using the 2 contactors you already have, the connections to the contactors remain the same. You just need to remove the Star contactor and change the control circuit to pull in both contactors at the same time. Here is a good resource for understanding what you have and how it works.

Now, why do you want to change?

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Hello msjls2,

First to do is Check the leads labeling, if your motor is manufactured in U.S the leads are labelled with numbers from 1 to 6. If this is the case Then disconnect the motor from the Wye-Delta starter and connect the motor for D.O.L : L1 to 1-6, L2 to 2-4 and L3 to 3-5.Earth to Motor´s frame.

If the motor is manufactured by IEC Standards then the leads are labelled like U1,V1,W1,U2,V2 and W2 for D.O.L start: L1 to U1-W2, L2 to V1-U2 and L3 to W1-V2.Earth to motor´s frame.

Regards.

Petronila

 
thanks for your help guys, especially petronila just what i wanted.
 
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