An electrical connector assembly includes a socket and a plug. The method includes receiving data packets from a source node at at least one port of the destination node. In the beginning of the track-crossing operation, the optical system will enter the first DAC mode that a pre-stored slice level derived from a calibration process is accessed and converted by the digital-to-analog converter before being referred as the slice level in the first DAC mode. Connecting bars extend axially within the axle with lateral rods joined to the connecting bars at their distal ends, the bars commuting between segments of the commutator electromagnetic coils.