Safety controller and system using same

A plurality of safety controllers for providing a safety output to a target controlled system based on an input from an input device to thereby control operation of machine equipment, said safety controllers forming a safety circuit that supplies power to said machine equipment only when safety condition is maintained by said plurality of safety controllers, each of said safety controllers comprising:

• a plurality of safety output parts for transmitting a solid-state output as said safety output;
• a connection output part for transmitting a connection output to another safety controller;
• a control part for carrying out input process, diagnostic process and output process according to a program, said control part judging condition of input from said input device in said input process, carrying out self-diagnosis in said diagnostic process and controlling said safety output and said connection output based on results of said input process and said diagnostic process;
• a connection input part for receiving a connection output from another safety controller as a connection input;
• and
• a setting part for setting to enable and disable the connection input from said connection input part;
• wherein said control part judges conditions of input from said input device and of connection input from said connection input part in said input process, carries out self diagnosis in said diagnostic process and controls said safety output and said connection output based on results of said input process and said diagnostic process;
• wherein said connection output is a solid-state output for logical connection and said control part determines output conditions of said safety output and said connection output by a logical calculation on the input from said input device and the connection input from said connection input part in said input process and controls in said output process according to result of said diagnostic process said safety output and said connection output in a safe condition determined by said input process if there is no abnormality and in a predetermined output condition if there is an abnormality;
• and
• wherein said control part controls said safety output and said connection output by disabling said connecting input if said setting part sets for disablement.

A system comprising a plurality of safety controllers for providing a safety output to a target controlled system based on an input from an input device to thereby control operation of machine equipment, said safety controllers forming a safety circuit that supplies power to said machine equipment only when safety condition is maintained by said plurality of safety controllers, each of said safety controllers comprising:

• a plurality of safety output parts for transmitting a solid-state output as said safety output;
• a connection output part for transmitting a connection output to another safety controller, said plurality of safety controllers being connected together through the connecting output parts;
• a control part for controlling said safety output and said connection output according to a program based on the input from said input device;
• a connection input part for receiving a connection output from another safety controller as a connection input;
• and
• a setting part for setting to enable and disable the connection input from said connection input part;
• wherein said control part controls said safety output and said connection output based on an input from said input device and connection input from said connection input part;
• wherein said connection output is a solid-state output for logical connection;
• wherein said control part controls said safety output and said connection output by carrying out logical calculations according to said program based on said input from said input device and said connection input from said connection input part;
• and
• wherein said control part controls said safety output and said connection output by disabling said connecting input if said setting part sets for disablement.