Method and system for collecting PLC data

1 . A method for collecting data from a programmable logic controller (“PLC”), comprising:

adding a checksum to all PLC data points within a transaction;

collecting the checksum and the PLC data points; and

verifying the checksum.

2 . The method of claim 1 , where the checksum is added to the data points at the PLC stage.

3 . The method of claim 1 , where a polling program collects the checksum and the data points.

4 . A system for collecting data from a programmable logic controller (“PLC”), comprising:

a polling program that polls and collects data from the PLC; and

a data analyzer that verifies a checksum to ensure that the data collected within a transaction is current.

5 . The system of claim 4 , where the checksum is added after the PLC has updated all transactional data points.

6 . A computer-readable medium storing computer-executable code of a process for use in a computer system for collecting data from a programmable logic controller (“PLC”), comprising:

adding a checksum to all PLC data points within a transaction;

collecting the checksum and the PLC data points; and

verifying the checksum.

7 . The computer readable medium of claim 6 , where the checksum is added to the data points at the PLC stage.

8 . The computer readable medium of claim 6 , where a polling program collects the checksum and the data points.