forward/reverse/stop station

[apsmac]

for a three phase motor I know how its wired but I cant seem to come up with an answer to "how it works" like a definition hope you folks can help thanx

 

[jraef]

Are you saying that you have these 3 momentary push buttons controlling a reversing starter, and you are not sure of the control logic involved?

Eng-Tips: Help for your job, not for your homework Read faq731-376

 

[apsmac]

I know how the control circut is wired and of course the motor using three momentary switches and two motor starters
but I am looking for a basic explaination to explain to a co-worker

 

[itsmoked]

You mean like this?

A three phase motor runs on the basis that three phases inherently creates a rotating vector.

This rotating vector manifests itself as a magnetic field in the motor's stator.

This rotating vector rotates in a specific direction.

The stator's magnetic field induces a magnetic field in the motors rotor.

The two fields interacting cause the motor's rotor to spin.

The rotating vector's direction is defined by the angular relationship between the phases.

By reversing any two phases, the rotating vector will turn in the opposite direction.

This reverses the direction of the rotor motion.

All your circuitry essentially just reverses two phases to make the motor's shaft turn the other way.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com