Hello Guest it is June 25, 2019, 04:51:48 PM

Author Topic: VFD Speed Control  (Read 8140 times)

0 Members and 1 Guest are viewing this topic.

Online Chaoticone

*
  • *
  •  5,514 5,514
  • Precision Chaos
    • View Profile
Re: VFD Speed Control
« Reply #10 on: November 22, 2006, 02:01:36 PM »
What are you using to sense spindle speed? Is the motor to spindle gearing one to one?
;D If you could see the things I have in my head, you would be laughing too. ;D

My guard dog is not what you need to worry about!
Re: VFD Speed Control
« Reply #11 on: November 22, 2006, 02:13:15 PM »
I am not using anything the sense spindle speed.  The computer is hooked to a spindle speed control via serial port and that is hooked to the VFD and the VFD tells the spindle how fast to turn.

Online Chaoticone

*
  • *
  •  5,514 5,514
  • Precision Chaos
    • View Profile
Re: VFD Speed Control
« Reply #12 on: November 22, 2006, 02:32:23 PM »
I wish I knew more about this for you. I had asked earlier if the gearing is one-one. I think it is direct drive isn't it? I think that with two adjustments that could be causing a problem, I'm not sure though. Some one will help clear this up for you. I'm going to send one of the smart guys a PM for you. ;D
;D If you could see the things I have in my head, you would be laughing too. ;D

My guard dog is not what you need to worry about!
Re: VFD Speed Control
« Reply #13 on: November 22, 2006, 02:47:30 PM »
There is no motor.  Its just a spindle controlled by a VFD.

Online Chaoticone

*
  • *
  •  5,514 5,514
  • Precision Chaos
    • View Profile
Re: VFD Speed Control
« Reply #14 on: November 22, 2006, 02:54:55 PM »
Yes, that is what I was talking about. All one piece. Maybe help will be here soon.
;D If you could see the things I have in my head, you would be laughing too. ;D

My guard dog is not what you need to worry about!

Offline chad

*
  • *
  •  361 361
  • When the going gets weird, the weird turn pro.
    • View Profile
Re: VFD Speed Control
« Reply #15 on: November 22, 2006, 03:05:42 PM »
Hey, what speed controller are you using? Could you tell us exactly what equip you are using and how it is all connected?

It should be possible to get it dialed in. On my big mill I just set the vfd at 18000 and switch it on and off. On my little mill i have a grex, so i use the analog out and it works pretty well.  I know that doesn't help , sorry, i have not used the serial control yet but we should be able to figure it out.

Chad
Re: VFD Speed Control
« Reply #16 on: November 22, 2006, 03:37:51 PM »
The controller is Sound Logic's new speed controll board.  It runs off the parallel port. It uses a chargepump to control the speec controller.  The VFD is a AC Tech.  So it is connected like this:

Computer serial cable connects to the Sound Logic Speed controller which is connected to the VFD which hooks to the spindle.

Offline chad

*
  • *
  •  361 361
  • When the going gets weird, the weird turn pro.
    • View Profile
Re: VFD Speed Control
« Reply #17 on: November 22, 2006, 03:57:00 PM »
Ok so lets just assume for the moment that mach is sending what it should to the speed control. 

The first thing i would do is make sure that the speed controller is scaling linearly with mach.  Set mach to 0 to 10000 max spindle speed. turn off the vfd and get your scope or volt meter out and look at the analog out of the speed controller.  If you set mach S1000 you should get 1v s5000 should get you 5v. Look at that then we will go from there.

Chad
Re: VFD Speed Control
« Reply #18 on: November 22, 2006, 04:10:03 PM »
at 10000rpm it reads 10.000 at 75000rpm it reads 7.2 at 5000rpm it reads 4.64  and at 1000rpm u get 1.02
« Last Edit: November 22, 2006, 04:12:18 PM by Smackre »

Offline chad

*
  • *
  •  361 361
  • When the going gets weird, the weird turn pro.
    • View Profile
Re: VFD Speed Control
« Reply #19 on: November 22, 2006, 04:50:23 PM »
Boy that is strange. As much as i hate to pass the buck i would recomend giving bob a call and see what he says. I sounds like an issue in his board or in the charge pump.
It should be linear..

Chad