Hi, I've built my LeadCNC 1515 and as I powered up the system I immediately noticed a lot of noise coming from the stepper motors. Now, at this point I had not even power up the VFD - so the noise is only from the 24DC power. Trying to connect to the USB from the breakout board (BoB) was, not surprisingly, unsuccessful - Windows did not recognize the USB device and the orange comms error lit up the BoB. Now, could I get your advice in how to minimize noise from my setup? I'm pretty sure it's just not grounded properly - but not sure what best practice would be. In the attached pdf "My CNC schematic" you can see the schematics as I have built it. Main components are: - STB5100 breakout board - 4-off TB6600 stepper drivers - 4-off Nema23 stepper motors (high torque) - Transformer 230VAC to 24DC - VFD - 1.5kW - Spindle - 1.5kW The schematics are based on the STB electric wiring diagram (attached) and the STB5100 installation guide from DreufelCNC. In my head I thought that the common ground to earth would run via the VFD control cable and that this ground wire would be connected to the 230V earth. But this is not the case. So I'm wondering how to set this system up to have it properly grounded/earthed? Thanks for any response!
Step 1) get a BlackBox and Xtension Limits with a Meanwell PSU Step 2) (Optional should just work. FAQ page exists for edge cases that do have issues, most often caused by bad wiring practices) : see docs:blackbox:faq-emi [OpenBuilds Documentation] BlackBox was built with onboard filtering. Extreme cases of EMI can of course still cause issues. But its usually a user error like neglecting to Earth the spindle body.
Thanks @Peter Van Der Walt - I have been looking at the Blackbox already, but thought I would try this setup first as it came easily available and allows me some trial and error without big consequences. After the hassle of connecting all of this together I probably should have just got it from the start. BUT: Then I wouldn't be forced into trying to understand what is inside the black box ;-) I have had a look at the "mitigating EMI" section previously, and also this nice article, but seem to fail on turning it into practice. I wonder where specifically more electronically gifted people would connect hook up the grounded for the electronics (BoB and stepper drivers) based on my current schematic?
So, after an afternoon of more troubleshooting the issue was not noise nor was is a faulty BoB. To my surprise it was the USB cable that came with the board which was faulty. Just as I was giving up I thought that I might as well try to use a different usb cable - you know, just to be sure I had tested everything...and a few seconds later the machine pops up on my computer! Hooked up the stepper motors one by one and everything was working, despite what I thought was a lot of noise from the motors Happy days - now to calibrate and fine tune everything before we start cutting stuff!! And complete the flip-top CNC work table:
so - a final update to give some lessons learned: After trying to calibrate and run the machine with the STB5100 BoB I got very unreliable results. The motors didn't sound very happy and when running GCODE the results were not consistent. A circle would end up like a spiral. And the scariest thing was when suddenly the slave motor on the y-axis didn't run and I had to jump on the emergency stop before seriously damaging the CNC! What did I do? Not wanting to waste any more time I ordered a Blackbox unit and waited for it to arrive. Took me an hour to re-terminate the motors and switches and set up the machine in OpenControl. Had it running like a symphony orchestra shortly after. Ran a test program and this time the results where as reliable as German machinery. What should you do? For the learning experience it was quite useful to tinker with the China-board - but if you want something that just works, get the Blackbox!!
