Possible buildbotics RS485 port bad (fixed, pwn vfd bad)

Anyone out there know how I might test the RS485 port on a buildbotics controller. I suddenly fell into the “timeout” on tool config for my spindle. I have triple checked continuity of wiring from back of breakout DB connector to VFD. I have purchased a new VFD and same issue. I have checked programming of both VFD’s far too many times and they both run manually fine, but no joy via com port. I have asked 1F support for any method to test controller port, but they say they will not support the controller port regardless of what is connected to it, as they do not offer any kind of technical support for unsupported spindles via their information they mention many, many times on all their documentation. Further they have no offering on how to test the port on the BB (as, of course, it’s not technically supported). Yes, the breakout has good continuity. Anyone have a controller they want to sell or allow me to test for my situation? Any help appreciated.

Hey Joe,


I would add, just checked both pins 13 and 14 to ground, (pin 19) at the breakout and read approx 2VDC when connected to the VFD on both wires. When disconnected from the VFD they are 1.5VDC and 3.2VDC, which I think is a good read. So I temporarily added a new harness and all is well. I think pin 14 found a short somewhere.

Ah yes, I had gone through all of that but never checked continuity between the wires, just start to end. A 101 error I can only blame myself for. All is working well now. Thanks.

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I have had the same issue with two different buildbotic controllers. I am not an electrical type, were you able to fix your problem?

I did, the issue was the Comm port on the spindle motor VFD.

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Were you able to fix your issue? Pretty sure mines doing the same. The vfd is not communicating with the 1f, which says it’s disconnected.

I had to send it back pwncnc
They are saying that the problem is resolved. I had to have knee surgery and I will not need able to verify on my end for a week or so

Yes it was the vfd port. Replaced vfd

Good luck with the knee. Finally figured mine out, reflashed it twice, reinstalled the firmware, and then had to swap the wires in the modbus cable again. Spent a lot of time with Nick from PWNCNC.

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Have you solved the issue. I’m having the same problem. I’ve reflashed the sd twice, swapped the wires inside the breakout box( pins 13/14), connected to the “run” port, removed the standoffs on the controller’s female connector, and the problem persist.

I did, and that’s what I had to do in my post above. Couple other things I noticed though before I did anything, the communication status said disconnected before I reflashed it and reinstalled the firmware. Once that was done, the status went to timed out. I then swapped the wires on 13 & 14. Make sure your wires are tightened down properly, I had a tough time getting a good connection with them. Once that was done status went to ok.

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