Very Basic Eaton MVX9000 VFD Questions

[tteess]

Hello,

I'm familiar with VFD's, but have never actually used one. I am trying to help someone who is using the MVX9000 as a single to 3 phase converter for a wood shop.

The tool we want to power has a magnetic starter. I have read that it's best to wire the VFD output directly to the motor and remove the magnetic starter from the circuit entirely. He tried leaving the magnetic starter in the circuit and says he hears a clicking sound from the starter when he attempts to start the tool.

First question: is there general agreement that it's best to just wire directly to the motor and remove the magnetic starter completely?

After reviewing the MVX9000 manual (http://www.galco.com/techdoc/chgp/mvx9000_um.pdf) I'm confused on using the digital inputs to start/stop the VFD. Page 3-6 shows the Control Terminal Wiring (Factory Settings). I only glanced at the drive when I was physically in front of it, but I did not see any wiring on the control terminal at all. I think the drawing is indicated that connecting DI1 to DI6 will start the drive and removing the connection will stop the drive. I did refer to section 30.11 as well, but it did not clear up my confusion.

Second question: to start/stop the drive do I just need to close/open a connection between DI1 and DI6, or is there more to it than that?

Any help you guys can provide would be greatly appreciated.

Thank you.

 

[Jraef]

Yes you need to remove the starter and wire directly from the VFD to the motor, assuming you meet all other code requirements of course. But for all intents and purposes, the VFD is the motor starter now. It turns it on and off and it contains the motor overload protection.

DI1 and COMMON will start the motor when closed, DI6 is for an external reset. DI1 alone, depending on programming, will give you what is called 2 wire control. Closed, it runs, open it stops.. If you want 3 wire control, i.e. a Start / Stop push button, they show how to wire it on page 5-13.

 

[tteess]

Thanks for the help. For the benefit of anyone who might read this in the future I learned there is one more thing you must do to make this work.

The factory default value of parameter 20.04 assigns the source of the operation commands to the keyboard. This parameter must be changed if you want to control the drive from the external control terminals.

 

[ptonsparky]

dang directions...always getting in the way of quick easy install