Many facilities that use PLC or DCS systems are locked into HMI software contracts with specific manufacturers that are difficult if not impossible to break. Yet most of these proprietary HMI systems offer export features to Excel for the benefit of data analysis that otherwise would be difficult to do in the native HMI environment. Given the ubiquitous role of Excel in facility engineering analysis, the program can be made to function as a dedicated HMI substitute or replacement utilizing common Modbus communications and Modbus active-x add ons, coupled with some minor Visual Basic programming.
Robert Benz,President,Benz Air Engineering, Co., Inc.