Entry-level Programmable Logic Controller (PLC) CPU unit with built-in I/Os - Mitsubishi Electric (MELSEC-F (FX) Series FX3S) - 20I/O [12DI (12 x digital inputs (24Vdc; Sink/Source)) + 8DO (8 x digital outputs (5-30Vdc; Source; 500mA; 0.2ms response))] - 4Ksteps (EEPROM; Program) memory capacity - connection capacity 30 x I/O points - with USB connector + screw-clamp term. connections (I.O's) - with RS-422 communication capability - Supply voltage 24Vdc - DIN rail mounting (75mm width) - equivalent to FX3S20MTDSS