1. enter a relay (x)
Enter relay is specifically designed to receive the input signal in the PLC‘s internal virtual relays. It was done by a PLC works relay function. It is inside the PLC connected to the input terminals, it has an infinite number of normally open and normally closed contacts, these dynamic, fixed broken contact in PLC programming, free to use. This input relay will not program driven, driven only by the input signal.
FX series PLC input relay using an octal number. FX2N series PLC with extensions up to a maximum of 184 point input relay, its number is X0 ∽ X267.
2. output relay (Y)
The output relay is designed to result in the PLC signal output interface circuit and output terminals serve virtual relay and control an external load. It is directly connected to the output interface circuit in the PLC, which has a myriad of dynamic contact and breaking contact, these moves and break contacts in PLC programming, free to use. External times there is no direct drive relays, it can only use the program drive.
PLC ONE 