Abstract: A safety device of the invention includes at least one of an input unit having one or more input terminals and an output unit having one or more output terminals, a testing unit having one or more test terminals, a rewritable nonvolatile memory configured to store setting information of a terminal specification which can be set from outside via the tool, and wherein the terminal specification of the one or more test terminals included in the testing unit is determined in accordance with the setting information of the terminal specification.

Abstract: A safety master configured to communicate with a plurality of safety slaves over a safety field network or with a plurality of safety local I/O units connected by a safety back plane bus of the safety master, wherein each of the plurality of safety slaves and safety local I/O units allow connection to safety I/O devices in a plurality of cell equipment, and wherein the safety master receives a status signal indicating a “safe state” or an “unsafe state” related to cell equipment from each of the corresponding plurality of safety slaves or safety local I/O units, and controls operation/stop of cell equipment by executing an interlock operation program with the received status signal as an input to output an operation instruction signal.

Abstract: A safety master configured to communicate with a plurality of safety slaves over a safety field network or with a plurality of safety local I/O units connected by a safety back plane bus of the safety master, wherein each of the plurality of safety slaves and safety local I/O units allow connection to safety I/O devices in a plurality of cell equipment, and wherein the safety master receives a status signal indicating a “safe state” or an “unsafe state” related to cell equipment from each of the corresponding plurality of safety slaves or safety local I/O units, and controls operation/stop of cell equipment by executing an interlock operation program with the received status signal as an input to output an operation instruction signal.

Abstract: This invention provides an input device of safety unit which enables an error diagnosis result referred to in a process of input processing for generating a control data from raw input signal to be referred by a side using the control data also in a safety unit such as a safety master and safety slave. An input device contains a function of outputting status data indicating the error diagnosis result referred to when input signal is converted to control data and the control data obtained by the conversion in pair, so that when the logical value of the control data is “LOW”, whether it originates from that the raw logical value is “LOW” or that “LOW” is compulsorily set due to an error in the terminal can be determined from the logical value of the status data.

Abstract: A remote I/O system includes a plurality of slave stations, and a mater station. The master station includes a communication failure detector configured to assume that a communication failure occurred when the master station has not received a reply from a failed slave station among the slave stations. The master station has, as a failure operation mode, a partial communication halt mode where the master station stops communicating with the failed slave station, allows the failed slave station to maintain the communication failure by not performing a communication resuming process on the failed slave station, and continues to communicating with the rest of the slave stations except the failed slave station.

Abstract: A network system for carrying out communication between a control station and a plurality of devices connected to a network. The communication includes data communication which requires real-time attributes and message communication which does not require real-time attributes. The data communication includes a first data communication, and a second data communication. The system includes a plurality of transmission queues for temporarily storing transmission data provided in the control station, wherein one of the queues holds transmission data for the second communication. After the first data communication is carried out in accordance with a predetermined cycle time, an appropriate switching between the message communication and the second communication is carried out in the remaining time of the cycle time to complete one cycle, whereafter the cycle is repeatedly carried out.

Abstract: This invention provides an input device of safety unit which enables an error diagnosis result referred to in a process of input processing for generating a control data from raw input signal to be referred by a side using the control data also in a safety unit such as a safety master and safety slave. An input device contains a function of outputting status data indicating the error diagnosis result referred to when input signal is converted to control data and the control data obtained by the conversion in pair, so that when the logical value of the control data is “LOW”, whether it originates from that the raw logical value is “LOW” or that “LOW” is compulsorily set due to an error in the terminal can be determined from the logical value of the status data.

Abstract: A safety device of the invention includes at least one of an input unit having one or more input terminals and an output unit having one or more output terminals, a testing unit having one or more test terminals, a rewritable nonvolatile memory configured to store setting information of a terminal specification which can be set from outside via the tool, and wherein the terminal specification of the one or more test terminals included in the testing unit is determined in accordance with the setting information of the terminal specification.

Abstract: A network system for carrying out communication between a control station and a plurality of devices connected to a network, wherein such communication includes data communication which requires real-time attributes and message communication which does not require real-time attributes, and wherein the data communication includes a first data communication in which data is transmitted from the control station to the devices and data in response to this transmission is transmitted from the devices to the control station, and a second data communication in which data is transmitted from the control station at a prescribed timing, includes a plurality of transmission queues for temporarily storing transmission data provided in the control station, wherein one of the queues holds transmission data for the second communication; wherein after the first data communication is carried out in accordance with a predetermined cycle time, an appropriate switching between the message communication and the second communicati