Can a 3 phase motor that is running on single phase have 2 directions?

[mfitch]

I am needing to know if this wiring diagram is showing a few things:

1: Does this show a 3 phase to single phase conversion?

2: Does this show that the motor can turn in 2 directions with the same internal wiring if you toggle the SPDT switch?

 

[Darkwood]

Although it is possible to create 2 additional lagging voltages from single phase to run a 3ph motor it is not normal to do so and not that efficient, there is no indication or representation of that in this diagram so although it lacks info it must be assumed it is a single phase motor, whether the diagram is correct will depend on the motor and winding arrangements which we are not given.

What is the query for, is this hypothetical?

 

[mfitch]

Although it is possible to create 2 additional lagging voltages from single phase to run a 3ph motor it is not normal to do so and not that efficient, there is no indication or representation of that in this diagram so although it lacks info it must be assumed it is a single phase motor, whether the diagram is correct will depend on the motor and winding arrangements which we are not given.

What is the query for, is this hypothetical?

Company dug up a hand drawn wiring diagram from 20 years ago and no one can determine if the motor can go 2 directions.

 

[Darkwood]

Can you take a pic of the plate or terminal arrangements, the diagram is as basic as you can get and little info' can be read off it accept for the obvious it suggests it is dual direction.

 

[mfitch]

Can you take a pic of the plate or terminal arrangements, the diagram is as basic as you can get and little info' can be read off it accept for the obvious it suggests it is dual direction.

correction, the motor is a wired single phase (3 wire) from factory. I was told wrong, this motor does not need 3 phase

 

[mfitch]

Can you take a pic of the plate or terminal arrangements, the diagram is as basic as you can get and little info' can be read off it accept for the obvious it suggests it is dual direction.

Here is the wiring diagram for the motor.

 

[Darkwood]

The diagram shows the power circuit but is missing the control circuit, it is questionably designed but hard to clarify from just the power circuit layout but for your feedback it does look like either a two speed motor or a dual direction motor, your other pic would suggest the latter is true here.

 

[mfitch]

The diagram shows the power circuit but is missing the control circuit, it is questionably designed but hard to clarify from just the power circuit layout but for your feedback it does look like either a two speed motor or a dual direction motor, your other pic would suggest the latter is true here.

That is exactly what I was needing to know thank you very much

 

[Marvo]

It shows a motor that is and always was single phase. As per Darkwood it's a bi-directional motor with an integral thermal overload that will auto reset.