Patent ID: 7472106

Claim:
A safety slave connectable to a safety network, the safety slave comprising: a safety information transmitting function of transmitting safety information determining whether a safe state corresponding to safety of a human or a dangerous state corresponding to danger to a human exists, corresponding to a demand transmitted from a safety controller through the safety network; non-safety information storing means for storing non-safety information about the safety slave; storing means for storing a fixed condition for transmitting the non-safety information; monitoring means for determining whether the non-safety information stored in the non-safety information storing means satisfies the condition or not; determining means for determining a transmission timing based on a monitored result of the monitoring means, wherein said fixed condition is corresponding to a life expectancy of a safety device connected to said safety slave; and a function of transmitting at least the non-safety information at said transmission timing when said monitoring means determines the non-safety information satisfies said fixed condition wherein transmission of the non-safety information is performed in one communication cycle based on the demand after safety slaves other than the safety slave finishes safety response, the safety slaves other than the safety slave being connected to devices other than the devices connected to the safety slave.