Single Phase Motor 3 Phase Starter

jap

Senior Member
I never was one to break the neutral through a 3ph starter if it was feeding a Single Phase Motor.
If the Motor was 240v Singlephase I have seen A phase landed on on L1 and A phase out on T1 and then B Phase in on L2 out on T2 in on L3 then to the motor on L3.
A Cutler Hammer Starter Instruction I was looking at a while ago showed this also.

Most of my career has been strictly 3 Phase installations and hardly ever single phase motor control.

I was just wondering what you all did.
Do you break the neutral through the starter? Neutral Directly to the Motor the Phase through one contact only or Phase and Neutral Looped through the Starter?

The Instructions do not differentiate between a 120v or 240v Single Phase installation.

Just that the Loop Jumper must be installed.
 

Besoeker

Senior Member
Location
UK
I never was one to break the neutral through a 3ph starter if it was feeding a Single Phase Motor.
If the Motor was 240v Singlephase I have seen A phase landed on on L1 and A phase out on T1 and then B Phase in on L2 out on T2 in on L3 then to the motor on L3.
A Cutler Hammer Starter Instruction I was looking at a while ago showed this also.

Most of my career has been strictly 3 Phase installations and hardly ever single phase motor control.

I was just wondering what you all did.
Do you break the neutral through the starter? Neutral Directly to the Motor the Phase through one contact only or Phase and Neutral Looped through the Starter?

The Instructions do not differentiate between a 120v or 240v Single Phase installation.

Just that the Loop Jumper must be installed.
I've done this before. You have live and neutral.
Neutral straight to the motor.
Live through all three poles of the starter contactor and overload connected in series. Otherwise it will see an unbalance between the "3" phases it's looking for.
It works but I don't know if it contravenes any code you have to comply with.
 
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