Hi all and happy new year, I am new to this forum, so let me quickly introduce myself. I am Fons, from The Netherlands. Although I did study applied physics, I have not been working as engineer for last 12 years. Setup: Workbee (Bulkman3D) + Blackbox + Interface + (VFD + Spindle / Makita router) Issue: Interface behaving strange when applying Cancel button. Spindle moves randomly, and random things appear on dispay (like setting zero menu, or tool menu). What have I done: Step 1: This week I got the whole thing finally set-up and running. Without spindle/VFD, everything was running fine. Adding the spindle, lots of issues which are mostly due to interference (as expected) Step 2: Attach the shielding to the earth star, using the new earth pin of the house, which is tested and working. New trial run. Now it also runs with interference without the spindle/VFD on. That does not seem to be an improvement. Observation, without spindle/VFD the interference gets worse when earthing. Hypothesis: grounding of house introduces signal. Possible due to long distance and ground and 220V running in combined line) Step 3: Attach the wire shielding (not spindle nor VFD) to ground pin located in workshop (sometimes it is nice that the building used to be a paper mill). Without stepper motors, everything works fine. I can push all buttons on the Interface and nothing happens, but also no missed commands or weird things. Step 4: Attach all stepper motors again. Everything is working, except for the cancel button. When that is pressed for a few seconds, random movement or random things on the display. Sometimes the CNC goes for long drives and I am happy I have an emergency button right there... But as long as the Cancel button is not pressed happy times. Switches work, spindle works, no problems. The issue is not there as long as there are no stepper motors attached. Remove everything (sensors/switches/spindle/vfd) and add a single stepper motor to the blackbox and the problem is there, even when grounding the shielding on the stepper motor. The power supply (meanwell) is grounded to the house pin. Grounding the shielding to the house pin freezes the Interface instantly. What is happening here?
Probably EMI. Is that spindle and VFD properly Earthed? Update to firmware 1.51. Move Interface out of the shop, boot it up on USB power. On the big logo during the boot process, hold the MODE button. It will enter self-test mode. Follow on screen instructions to test all the hardware. If it works away from the machine, you know the source of interference is from something connected to the machine
Hi Peter, Will try tomorrow. Issue also occurs with the VFD and spindle being completely disconnected (no 220V line into VFD). Earthing the VFD made no difference; it is currently earthed though. Thanks for the quick reply. Regards, Fons
Ok test results are in: Self test completed fine. No errors. Same result in workshop with equipment turned on. Conclusion: the problem is not with the electronics themselves but with interference (as expected). Next step was to remove as much as possible contributions to the problem. The minimum setup is: bb+interface+cable+stepper motor. Therefore I removed one stepper motor from the machine, and retrieved one of the connecting cables as well, and hooked it all up. Aim is to find out what is causing the problem: Tests & Results: 1. Attach cable to blackbox: no problems observed. Normal operations, although of course nothing is being driven as nothing besides the cable is connected. 2. Attach motor to blackbox: no problems observed. Motor operates as expected, and all functions on the interface work as expected. 3. Attach motor to cable to blackbox: no problems observed. Motor operates as expected, and all functions on the interface work as expected. 4. Attach the cable shielding to: a. house earth pin: motor operates, but with issues when using the cancel button. b. shop earth pin: motor operates, but with issues when using the cancel button. c. holding it in hand: motor operates, but with issues when using the cancel button. 5. Voltage between powerline of house and earth pins is in both cases 230V as expected. What we know from this: 1. Problem is indeed interference related. 2. Interference is either caused externally in the environment, or generated by the single stepper motor. Questions: 1. Based on the above results is it safe to assume the ground pins are working as intended? Earth breakers in our house do trip in case of mishaps ;-) 2. What to do next ...
In that case it works fine. Need to test what will happen with no shielding, and the VFD turned on though. Will test
Test results are in: with shielding disconnected, and VFD in standby (so spindle not spinning): massive interference.
VFD not connected to power supply: no interference, as long as not shielded, or not connect to earthing.
I like your detailed test reports Yeah we don't shield motor wiring, so that should help. Regarding the VFD, is the PE terminal inside the VFD connected?
Okay the test setup for this was: blackbox + interface + steppermotor (no shielded cable in the middle). 1: VFD standby, not ground: interference. 2. VFD running, not ground: interference (as expected). 3. VFD standby, grounded: no interference. 4. VFD standby, grounded to workshop pin: no interference (confirming that both pins work). 5. VFD running, grounded to either pin: interference. This was the reason for originally grounding the shields to earth.
This one may take some work. Some of those chinesr VFDs really are noisy. I'm afraid you'll have to try a Faraday cage / enclosure around the VFD. For what its worth some VFD installs are quite fine, we can't figure out if really boils down to particular VFDs or how they are installed.
True. But even without the VFD on I do not get reliable operation. I have a Makita rto700cx3j, with the required mounting brackets. I just stayed in the shop for a bit longer to assess whether that was feasible. Still using the single motor setup, removed all the connections to the VFD etc. The most stable I can get it is with the shielded wire not earthed, but that still gives me errors; just less frequently so that I did not observe them earlier. This means that even abondening the VFD/Spindle combo for the moment, is not going to resolve the issue, as I still get interference on my single motor setup. So faraday cage will not help I am afraid.
Did some further experiments just now. Instead of using the controller I am using my pc to control the whole lot. No problems seen so far. Hitting the abort button does not result in any weird behaviour this time around. not sure what to think of this.
