Oz, Please elaborate.
Are you saying from your experience, that in this case you mentioned there is a need to ground the USB shielding itself? cause it looks like it is floating - the wire shielding itself is not connected to main 24V DC Minus terminal. I am not sure if what i’m doing is right, but the fact that I have grounded the USB extension cable’s shield ON BOTH ENDs of it made the change. i am still checking things out but you can’t argue with the statistics:
- When USB shield is floating - Smoothie resets when Pump starts
- When USB shield is grounded - Smoothie does not get reset when Pump starts
It looks like Pump is somehow generating emi that rides on the long usb extension cable shield (which if not grounded radiates onto the communication lines) , gets amplified and effects communication lines.