Modifying data as it passes from one program to another
A consulting company needed a quick and easy way to modify data as it passed from one system to another. They were using the OPC DataHub to connect from an OPC server to a Java based Web display, but due to problems with some of the sensors reading data from the field devices, certain values needed to be cleaned up before they were displayed on the web. A simple DataHub script was written that watches for changes in point values and if any of them read a max off-scale value of say -524455, then the script replaces the value with a zero. This helped to clean up the web display of data and provided the company with a fast and effective way of conditioning the process data to meet their requirements.