Re: [CAD_CAM_EDM_DRO] variable control with inverter

carlcnc@... wrote:

> I use a VFD to run a hi frequency spindle. I have always set my
> speed[freq.] via the digital keypad.
> However, the inverter will accept analog signals for speed control,
> either 8 pre-sets or proportional for true variable.
> What do I need to buy/build to use something like a 10 turn pot
> so I can adjust on the "fly"?

Consult the manual for this info. it is somewhat different for each
model. Some have 4-20 mA current loop, some have 0-10 VDC,
some have a reference supply so you can just hook up a pot to
3 terminals. but, you really need to check the manual. You will
have to reprogram the control to accept the analog speed command.

What type of spindle do you have, and does your VFD go above
400 Hz? I have a Westwind air bearing spindle that can go up to
1200 Hz or so, but I don't have a VFD that goes above 400 Hz.

Jon