More info
This 3-pin to 7-pin cable for the Nucleus-M allows you to power the motors from 3-pin power while also giving you run/stop capabilities in camera systems that support it. To power all of the motors, simply plug this cable into one of the motors and then daisy chain power to the other motors using the Nucleus-M 7-pin to 7-pin power cables.
Note that this cable was specifically designed for the Nucleus-M so the R/S function only works with the Nucleus-M’s own hand unit and handles.