"PWM Bumped to Minimum Setting" message

[rickturner646]

Team,

I'm having trouble getting the speed on my mill to match what is set in the g-code, and when I do so I get the information message in Mach "PWM bumped to minimum setting". I cant find any explanation for this message in the docs or online, so can somebody please tell me what it means, and how I fix it?

The speed problems I am having are a bit odd. If I put say 'S500' into my g-code, the mill will start up at 740 rpm. If I put S900 into the code, then I will still get 740 rpm. If I then use the manual override in Mach, and boost the speed, it will do nothing for two or three clicks and I will end up with a situation where Mach says 'normal speed 900', 'speed override 1140', and a mill still doing 740 rpm...... At some point, the speed override does kick in but incorrectly - in this case, upping it again to say 1200 manually will make the mill jump to maybe 1420 rpm. This is driving me nuts, as you might imagine.

I've tried auto-calibrate on the spindle speed, but it simply does not work. Sits there indefinitely doing nothing.

All suggestions etc gratefully received!

Regards,

Rick
 

[Chaoticone]

Rick, Look in config., Spindle pulleys and tell what you see. What is the current pulley and min/max RPM value for it?

Brett

[rickturner646]

Hi Brett,

it's on pulley 1, min 300 rpm, max 3500 rpm, ratio 1.

Note though that the mill does not have pulleys - it's a Syil x4 so has a direct variable speed drive (300-3500 rpm, as it happens).

The config file is the one that Syil sent me, and this setting is one that came with it.

Rick

[Chaoticone]

Rick, tell us more about your set-up. What kind of beakout board, VFD, ect. your running. Also post your XML file so we can have a look. PWM is not true analog and although most analog VFDs will work with it, some don't like it.

Brett

[rickturner646]

Brett,

I am not sure who makes the boards for Syil, but I have asked them. Judging from the markings on the chipsets they are chinese made. The machines come pre-assembled so it's not as if I have sourced the parts myself.

I'll attach pictures of the stepper driver and interface boards here, perhaps you can recognise them.

I'll also attach the xml file as requested.

Regards

Rick