Hi Folks, first attempt at CNC and I'm having problems between the Blackbox and A2 8022 VFD with a 2.2kw water-cooled spindle. I've connected the VFD as per the guide here, I can now get the software to turn the spindle on at 24000 rpm, set the potentiometer at 400hz and then turn it back off again but when I try to lower the speed and run it, it stays at 24000rpm regardless of what I change. I've tried contacting the VFD manufacturer but had nothing back and I'm at a loose end. I could disconnect from the Blackbox and it works manually but it would be nice to have the function available. I've had a search through the forums but have not found any resolved posts, anyone had a similar issue or have any ideas of what to change? Cheers Dave
To determine if its a VFD or BlackBox issue: 1) Disconnect VFD from BlackBox 2) Connect multimeter in voltmeter mode to 0-10v output 3) Send various M3Sxxxx speeds and see if the 0-10v scales correctly If the 0-10v scales correctly, next step would be to check the VFD parameters
Thanks for the fast reply, as I say I'm a total newbie at this. I checked the voltage at M3 S24000 and M3 S12000 and it was showing 4.97 volts for both. I've had a look further into the software and noticed that the G30 and G31 commands were set at 10 and 1000. I've changed these to 4000 and 24000 as per the spindle specs and it now alters the voltage and spindle. What I have noticed is I keep getting random overload trips on the VFD. I'll have a further look into setting up the software tomorrow as that seems to be the issue. Thanks for the help, I'll update tomorrow in case it's of use to anyone else. Cheers Dave
Updates are always welcome! It really does help others Yes, overload trips are usually VFD parameters, or forgetting to set Minimum Freq (most spindles prefer 7200-24000, running too slow causes overloads too)
Sorry for the late follow-up had to put a hold on things getting ready for the holidays. To get the spindle to spin without the trips I had to alter PN11 (minimum runtime frequency, 116hz I think it was) to match 7200 rpm. To get the correct 10v output from the black-box (was sitting at 4.9 max) I had to alter the G31 & G32 to 0 and 24000. This now controls the spindle at the correct speed and the VFD will cut out if the RPM drops below 7200. Thanks for the advice, much appreciated. Now that the machine is setup and working I have realised I have no idea how to use it.
