Receiving unit with DC power supply. With 21 programmable MOSFET digital outputs + 2 relays + START and STOP, internal antenna standard or optional external antenna, 8 inputs for Data Feedback. 2 expansion slots are available for programmable relay boards, voltage/current analog output boards, digital and/ or analog input boards, variable resistive output boards, sync boards between receivers (Synchro), RS-232/485, CANopen, Profibus DP, PROFINET, EtherCAT® and EtherNet / IP™ serial communication port boards.