Connection Issue

[Andy_B]

Can anybody help with why i get his lost connection and will not reconnect
the odrive is in closed loop control

thanks in advance

[towen]

I think you have the same problem as ap23:

ODrive not recognized by computer with odrivetool

Yes, that definitely sounds like a noise issue, or possibly a ground loop. If the negative terminal of the power supply is referenced to mains earth (as it is with most power supplies), then you have to be careful that you don’t get a portion of the DC Bus current flowing via the USB cable. You could try shortening / twisting your DC supply cable, which will reduce its resistance and inductance, to provide a much lower impedance path so that less current flows via the the USB cable. Or use a…

Try the ferrite rings from the shop, and try twisting/shortening your cables if possible.

[Andy_B]

Hi Tom - your fast at this stuff

just tried odrive on 48v batt and laptop on batt (no mains connections) still keeps doing it - however it recovers if i spin the motor out

[Andy_B]

The usb cable that came with the odrive is not faulty - but using a shorter cable has solved all the issues

[towen]

interesting - what do you mean by “it recovers if i spin the motor out”?

I strongly suspect that the PWM switching edges are causing MHz-GHz range noise to be emitted from the big antenna that is your motor cables. A ferrite ring close to the ODrive with a couple of turns of your motor cable through it should absorb 90% of that.