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The term HART is great for bad puns



I was offered an unused ABB pressure transducer with HART interface (see http://www.hartcomm.org/). HART stands for Highway Addressable Remote Transducer. Showing the ability to read all values from such a device using Unitronics is an advantage for applications in the mining and resources sectors in particular.Using the Turck BL20-E-GW-EN and BL20-2AIH-I a simple ModbusTCP gateway module was possible. Whilst all HART values are accessible as Modbus registers, the conventional 4..20mA input value is stored as a 16-bit signed integer (MI) but the HART values are 32-bit Float values (MF). Also the Float registers must have the word order reveresed. I currently have a V530 program that reads all values and displays them on the screen. Using SB102 allows the word order to be reversed when reading the Floats.Two problems currently remain* The remote device does not appear to detect a lost connection, and doesn't automatically connect on power up. Not sure what is happening here, but it seems like the problem is with the remote device, as I have not had this much trouble communicating with other ModbusTCP devices from a Unitronics PLC.* converting the project to V350 mostly worked, but the reversal of the float words did not work - also not sure about that one, and haven't spent the time reading the help files for clues at this stage..


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