The CMD-CM3-10 has three separate Ground plans; use the correct ground reference for the input/output you are using. Note: It is possible, (not recommended) to connect all ground plans to a single point with the power wiring.


 Electrostatic Discharge (ESD) ring ground 
The ESD ring protects the controller from moderate ESD events. All metalized connectors (Encoder, USB, NP-Link, Commander case and Servo Drive mounting screws) are connected to the ESD ring. This should be connected to the Earth ground through the 6 mounting holes on the Printed circuit board (PCB).


Logic ground
The logic ground and motor power ground are shared and used as the reference for all on board signals, as well as encoder inputs, U axis outputs, and analog inputs.


Isolated (ISO-) ground
The ISO ground is used for all inputs/outputs for the CMD-CM3-10 controller unless otherwise noted.


No ground reference
Some outputs are fully floating so do not have a predetermined ground reference and are safe to connect to any ground reference. They include the Relay (MC) outputs, digital inputs, and General-purpose input/output (GPIO) 5 and 6. See the section below for more information on these outputs.