Ok, I'm trying to get my VFD to be hooked up on the G540, all driven by Mach3. So far I had no success doing so.

This is my setup:
1) I used "default" G540 XML configuration file which can be downloaded for G540. I was ensured bu many G540 users and Geckodrive support, that it should be ok.
2) I have G540 hooked up on VFD, (3 cables: +10V, 0-10V signal, COM)
3) I have VFD jumpered so it should go always forward (just for now) so I do not need relays for now.
4) I have spindle configured to be driven by PWM 50Hz, min 5%
5) I set up pulley with ratio 1:1 and max RPM 24000.
6) Spindle motor tuning: here is a first hicup. I have no idea, how to map steps, velocity and acceleration on spindle. It makes perfect sense for stepperes, not so for spindles.
7) When I try to punch speed into spindle and do CWF5, I see nothing. RPM says 0. Mach3 from some reason does not want to start spindle.
Funny is, when I check "average spindle speed" in spindle settings and then punch CWF5, RPM jumps to 24000 and then quickly ramps down to 0. 

When I measure +10V on Gecko, it really says +10V, when I measure 0-10V signal, it always shows 0.48V, which is pretty much 5% duty cycle.
So what am I doing wrong? What am I missing?

Thanks a lot for help.

You need to tell Mach what spindle speed you want. Either from MDI or code or you could type it direct into the spindle speed DRO.
From MDI or code it would be S followed by the speed you want, eg S500 would be 500RPM.
Hood

Thanks Hood for your suggestion. Unfortunately, I'm already doing this (Step 7 - punch speed in and then CWF5).
Any other ideas?

Yes but are yyou tring to type it into the correct DRO, you will soon know, if you tye it and press enter and it goes back to 0 then you are not, if it stays at what you typed then its the correct one.
Easiest is to just go to MDI and type M3S500 then press the enter Key
Hood

Ok, I moved one step ahead. I'm now able to get into the point there is 0-10V coming of the G540.

Issue was <you got to be kidding me>:
If you try to toggle spindle in the Mach3 without opening project, it will NOT start.
If you load up whatever project (you can even close it right away), from this point on you can toggle spindle till you exit application and start again.
Seriously!? If this is a feature, PLEASE, document it somewhere (best place would be tutorial), because I'm sure I was not first and I'm not going to be last. Otherwise, is this know bug?

Now I have to figure out, why my trial VFD (Huangyang) accepts input from HMI instead of Vin, even if it is configured the other way around (PD001 and PD002 changed from 0 to to 1).

Dont have a clue what you are on about with the project bit. If you are meaning open G Code then no you dont have to. I can switch spindle on/off any time.
Hood

Hood, yes, I mean G-code.
I will start up Mach3, I will toggle spindle. Nothing.
I will load up g-code, I can toggle spindle and I get output on the drive.

Dont know why that would be. Attach your xml and I will see if I can replicate the issue here.
Hood

Mach3 R3.043.022

Seems to be fine for me but I have 062 version loaded and dont have a ESS to test with.
Will load 022 and see if it makes a difference but cant think why it would.
Hood