Patent ID: 7286885

Claim:
A safety programmable logic controller (PLC), comprising: I/O modules, which are connected to safety devices, configured to detect a predetermined condition at any time and constructed to satisfy an individual connection specification of each of the safety devices, respectively; a CPU module configured to execute a safety program for managing the I/O modules; and a connector configured to interconnect the I/O modules and the CPU module with each other, wherein the CPU module includes a function block memory unit configured to store a plurality of function blocks which are separately prepared for the respective connection specifications of the safety devices, a ladder circuit configured to compute an output signal to be determined based on an input signal from the corresponding safety device being programmed in each of the plurality of function blocks, an ID number obtaining unit configured to read identification numbers of the I/O modules connected to the connector, and a program link unit configured to sequentially link the function blocks received from the function block memory unit based on the read identification numbers to create the safety program.