Patent ID: 7949418

Claim:
A safety PLC comprising: an I/O module to which a safety device for detecting a predetermined condition at any time is connected; a CPU module that executes a safety program for managing the I/O module; and a communication unit that interconnects the I/O module and the CPU module, wherein the CPU module includes: a PIN code memory that stores a PIN code for authenticating that the safety program satisfies a predetermined standard; a PIN code input unit that receives a user designation of the PIN code; a function block memory that stores a plurality of predetermined function blocks; a program auto-creating unit that automatically creates the safety program by combining the predetermined function blocks when the PIN code designated by the user coincides with the PIN code stored in the PIN code memory; and a program authentication unit that executes the safety program when the PIN code designated by the user coincides with the PIN code stored in the PIN code memory.