Programmable controller system

A programmable controller system, comprising:

• a programmable controller apparatus;
• a remote input and output apparatus connected to the programmable controller apparatus via a field bus;
• and
• a monitoring apparatus configured to be located on a communication path between the programmable controller apparatus and the remote input and output apparatus and passively monitor communication data therebetween,
• wherein the programmable controller apparatus including:
• an input unit for inputting a signal from an external equipment;
• an output unit for outputting the signal to the external equipment;
• an input and output memory having at least an input region for storing input data corresponding to signal inputted by the input unit of the programmable controller apparatus, an output region for storing output data corresponding to signal to be outputted from the output unit of the programmable controller apparatus, a remote input region for storing input data corresponding to signal inputted by the remote input and output apparatus, a remote output region for storing remote output data corresponding to signal to be outputted from the remote input and output apparatus, and a deterioration diagnosis flag configured to be referred in accordance with a user instruction;
• a program memory for storing a user program to which a preferable control specification is written in use of the user instruction;
• an input and output update part configured to carry out an input and output update process for transmitting and receiving data between the input unit and the output device unit of the programmable controller apparatus and the input region and the output region of the input and output memory via an internal bus, and a remote input and output update process for transmitting and receiving data between the remote input and output apparatus and the remote input and output update region of the input and output memory via the field bus;
• a deterioration diagnosis flag control part configured to control of turning on and off of the deterioration diagnosis flag according to a deterioration diagnosis result notified from the remote input and output apparatus via the filed bus;
• and
• a program execution part configured to execute a user program stored in the program memory with reference to the input and output memory and to rewrite the output region and the remote output region of the input and output memory according to an execution result,
• wherein the remote input and output apparatus including:
• an input unit for inputting the signal from the external equipment;
• an output unit for outputting the signal to the external equipment;
• an input and output update part for transmitting an input data corresponding to the signal retrieved by the input unit to the programmable controller apparatus via the field bus and transmitting the signal corresponding to the output data received from the programmable controller apparatus via the field bus from the output unit;
• a time lag measurement part for measuring a time lag between a signal edge of a terminal and the signal edge of an other terminal of one or more pair of terminals of the input unit or the output unit;
• a time lag register for storing a time lag of each pair of terminals obtained by the time lag measurement part;
• a deterioration diagnosis part for comparing a deterioration characteristic quantity generated based on the time lag stored in the time lag register with a predetermined threshold value and diagnosing deterioration of the external equipment connected to the pair of terminals;
• a diagnosis result notification part for notifying the deterioration diagnosis result obtained by the deterioration diagnosis part to the programmable controller apparatus via the field bus;
• a transmission request command processing part for transmitting, as a response, the time lag stored in the time lag register or the deterioration characteristic quantity generated based on the time lag to a originating device of the transmission request command in response to receiving the transmission request command via a message communication,
• a time lag measurement part for measuring a time lag (T1) between a signal edge of a first terminal in the output unit and a signal edge of the first terminal in the input unit and a time lag (T2) between a signal edge of the first terminal in the input unit and a signal edge of a second terminal in the input unit;
• a time lag register including a first time lag register for storing the time lag (T1) and a second time lag register for storing the time lag (T2);
• a deterioration diagnosis part for comparing the deterioration characteristic quantity (T1×T2) generated based on the time lag (T1) stored in the first time lag register and the time lag (T2) stored in the second time lag register with a threshold value (TH) to diagnose deterioration of the external equipment connected to the pair of terminals;
• and
• a command processing part for transmitting, as a response, the time lags (T1, T2) stored in the time lag register or the deterioration characteristic quantity (T1×T2) generated based on the time lags to the originating device of the transmission request command in response to receiving the command via the message communication,
• wherein the monitoring apparatus including:
• a transmission request command issue part for passively monitoring communication data transmitted between the programmable controller apparatus and the remote input and output apparatus to observe a signal state of the terminal of the input unit or the output unit of the remote input and output apparatus and issuing a transmission request command to request a transmission of the time lag or the deterioration characteristic quantity to the remote input and output apparatus via a message communication supported by the field bus in response to detecting an edge of the signal state in a predetermined direction;
• a data storing part for storing the time lag or the deterioration characteristic quantity from the remote input and output apparatus in response to the transmission request command to a memory;
• a stored data output part for outputting a data stored in the memory by the data storing part to an external apparatus in response to a reading operation,
• a command issue part for issuing a transmission request command to request the time lags (T1, T2) or the deterioration characteristic quantity (T1×T2) to the remote input and output apparatus via the message communication supported by the field bus in response to detecting the edge of the signal state in a predetermine direction;
• a data storing part for storing the time lags (T1, T2) or the deterioration characteristic quantity (T1×T2) transmitted from the remote input and output apparatus as a response to the transmission request command to a memory;
• and
• a stored data output part for outputting a data stored in the memory by the data storing device to the external apparatus in response to a reading operation.