Hi I am trying to setup a small router with LinuxCNC, Mesa5i25+7i76 cards and three Lichuan LCDA357H drives and LC57H380 3 phase motors with encoders.

I have them running as expected in open loop (switch 6 on) but they don't work in closed loop. There is a small movement and then a three flash error. (which the documentation doesn't cover but I am guessing is encoder related)

When I put the scope on the encoder inputs I just see 50hz line noise (a significant amount of it) I have everything on the machine ground with its own wire to a central point but the encoder wires do not appear to have a ground. I see the same noise if I check the mid cable connector in the encoder wires.

so far I am not impressed with these drives or motors based on the poor documentation alone.

does anyone have an idea of how to proceed?

thank you

Luke