Magnetic starter- wiring an Allen-Bradley 709 3-phase starter for single phase 220v.

[JimDawson]

If I understand correctly, you are planning on running a 5 HP motor on 120V? That is about 50 amps. It can be done, but is very unusual. Normally you would run that motor on 240V, that's still about 25 amps. Also that motor starter might be a bit light for 50 amps. I think you need at least a NEMA 3 starter for that much current. Your (NEMA 1) starter is rated at 27 amps continious.

 

[portsample]

(2) 120v wires are what the motor is designed for and what is currently running it. The switch on it now is a Grizzley paddle switch (non-magnetic) w/contacts too small for this motor.

 

[JimDawson]

(2) 120v wires are what the motor is designed for and what is currently running it. The switch on it now is a Grizzley paddle switch (non-magnetic) w/contacts too small for this motor.

I think there may be some confusion in the terminology here. At least I'm a bit confused) Does each wire measure 120 volts to ground or if you connect the volt meter across the two wires, does it measure 240 volts? If so then it would be 240 volt, single phase, standard house wiring.

 

[jim18655]

If you follow the diagram in your first post the neutral connects to L2 and the 2 hots to L1 and L3. The motor connects to T1 and T3 for 240v.
Jim D. is correct about the large current draw on that size 1 starter. I think you'll need a larger size even at 240v.

Single Phase Motors

Maximum horsepower, full voltage starting, two pole contactors, are indicated below:

Maximum Horsepower (hp)
NEMA Size	115 Volts	230 Volts
00	1/3	1
0	1	2
1	2	3
2	3	7.5
3	7.5	15

 

[portsample]

I think there may be some confusion in the terminology here. At least I'm a bit confused) Does each wire measure 120 volts to ground or if you connect the volt meter across the two wires, does it measure 240 volts? If so then it would be 240 volt, single phase, standard house wiring.

My mistake, yes it's 2 x 120v.

 

[JimDawson]

Gunrunner you need to order a set of these for the Z axis hand crank. Bill did you just spit coffee on your monitor? :rofl:

View attachment 253356

 

[portsample]

This works.

Thanks for the help.