Data Logging and Monitoring to Rockwell PLC

Data Logging The below gives information on one logging and monitoring data system. 19 of these sets of data (graphs) are to be logged and monitored simultaneously and stored for records. These should be in one program to run on one PC. All data will come from 1 Rockwell Logix 500 PLC Version 32. Each Graph will be identical in function, but have completely independent data and control. Any User Variables should be protected by a Password. Each monitor will log up to 5 data points. These will be selectable PLC tags. Frequency of logging i.e. scan time will be adjustable for each graph from 1mS up to 1 minute. Data sources will be PLC tags. Likely INT, DINT or REAL Logging will start using a handshake. E.g. PLC sends BOOL and a STRING to start monitoring for graph 4. Then monitoring program will echo a BOOL and the same STRING information to confirm it has started. This will maintain high whilst active. The string value will be individual and assigned to the filename for saving. Both BOOL values will remain high throughout. Whilst monitoring, it will be possible to setup limits for each data source, HI, LOW, Delay ON, Early OFF and Dwell. HI and Low will be the limit values. Delay ON and Early off will be to Delay the start of the limit monitoring and Ignore the last portion of monitoring. These will be adjustable time values. Dwell will be the amount of time that the value has to be outside of the monitoring tolerances before it will be logged as a fault. When logging is complete the PLC will send a COMPLETE bit and the logging bit will go low. The logging system will then echo a DONE bit and either a PASS or FAIL bit. The file should be saved with the filename given in the initial string and when the complete bit is LOW again, the logging system should be ready to start. Program will send an alive pulse to the PLC on a 0.5 second pulse i.e. high for 0.5 low for 0.5 The attached picture gives a rough example with three data points and the monitoring windows shown behind each data point.