Can expand PLC of port

The utility model discloses a PLC of expanded port, it includes main PLC (1) and extension terminal board (1), wherein: main PLC (1) has the box body shell, inside be provided with control circuit board (12) of box body shell the box body shell be provided with on the surface with the input output terminal row's that control circuit board (12) are connected wiring hole (11) box body shell top is formed with a recess (14), extension terminal board (1) wherein is provided with expander circuit board (22) including a receiver, the protruding extension terminal row (21) that is equipped with in its surface, the extension terminal row (21) with expander circuit board (22) electricity is connected, extension terminal board (1) is pegged graft extremely in recess (14) of main PLC (1), just expander circuit board (22) in extension terminal board (1) with control circuit board (12) in main PLC (1) are realized the electricity through plug -in element and are connected. Implement the utility model discloses, can expand