Help wiring switch to vfd.

Thanks for all the advice guys! The only reason I was talking about using shielded wire was because that's what the O.M. called for. I guess these vfd's are very sensative to voltage leaks etc. At least that's how I read it, but you guys are saying not to be to concerned with it. I will not be running the wires in a conduit as I may need to move the lathe from time to time. I was going to run a ground wire from the motor housing to the vfd ground termination point. I purchased a 4 pole twist lock plug set and I was going to use that for the motor power cable between the vfd and the motor. These vfd's have got to have the crappiest manuals and instructions I have ever seen, LOL.
Input wires, got it.
output wires, got it.
switch wires, got enough to figure it out I think, the switch diagram was a big help!
God help me when I try and wire a variable speed pot, LOL.
Oh well this is all new to me, I can wire a house no problem, but figuring out electronics.........still learning I guess.
Thanks to all for your help and patience with me on this important step.
 
I went to a large electrical supply house by me that has everything electrical, from small to industrial. They did not have the 14/4 shielded wire either, so based on the advise of others here I purchased a very good rated at 600 volt 14/4 rubber covered wire for the 3 phase power cord from the vfd to the lathe. One other question I have is should the power cord be grounded at the vfd and at the motor also? I think it should be. The motor was not grounded when I got it and I was going to ground it with one of the cover screws. The reason I ask this is the O.M. states that the shielding should only be grounded at the vfd.
 
That's correct Greg.

The shielding should only be grounded at one end, but the motor should have a dedicated safety ground regardless. You said yours did not have one, neither does mine. Just find a screw or bolt close to the motor, mounting bolts work fine, and attach it there. Make sure that you have a good connection, preferably using a star washer to really get the best contact.

You wont have any problem running without the shielded wire.

-Cody
 
Awesome! Thanks that's what I thought, gonna go play with some wires now.
 
The vfd is wired and so is the switch, a little fiddlin with the parameters and she's up and running and uses the original switch for forward, off, reverse.
I do have a couple of questions though....what a surprise. I have the upper set at 60 hrtz and the lower set at 50, can the lower be safely set any lower or should I leave it there?
Second, Unless I pull the disconnect the vfd is always on, is this normal?
I do see myself getting a speed pot for this thing, it just works too good. I ran it for about a half an hour and it didn't even get warm.
 
Hey Greg,

You can safely set the minimum frequency at 0. It is generally not recommended to run motors for long periods at very low frequencies, due to overheating, so I usually use about 20-30. If you leave the minimum too high, you lose the benefits of a VFD.

And yes, it is completely normal for the VFD to stay on, even when not running. Just power it up via the disconnect when you start working, and shut it off when you leave. Avoid repetitive cycling on and off.

-Cody
 
Codered741 said:
Hey Greg,

You can safely set the minimum frequency at 0. It is generally not recommended to run motors for long periods at very low frequencies, due to overheating, so I usually use about 20-30. If you leave the minimum too high, you lose the benefits of a VFD.

And yes, it is completely normal for the VFD to stay on, even when not running. Just power it up via the disconnect when you start working, and shut it off when you leave. Avoid repetitive cycling on and off.

-Cody
Click to expand...
Thanks for all your help Cody, I really appreciate it, vfd's are all new to me, but man are they cool! I'll get the lower range reset a little lower. So if I pull the disconnect it won't loose it's memory?
 
No problem Greg! I'm sure that I am going to have a bunch more questions as I get further into my rebuild. So I figure that I'm just paying you back ahead of time.

Your VFD should not lose its memory when you shut it off, but check the manual for any thing like that.

-Cody
 
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