The Motor Brake Cable can be attached directly to the 400V version of the V90. The 200 V version requires an external relay to connect the motor brake cable. The relay must be connected via the setpoint cable for the SINAMICS V90 pulse train version and via I/O cable for the SINAMICS V90 PROFINET version. I/O cable is necessary for the brake control of the SINAMICS V90 PROFINET 200 V version, and for applications requiring additional DI/DO in addition to PROFINET communication.