Protocol-based non-invasive Modbus monitoring device for industrial internet of things data sharing

The traditional Modbus communication architecture usually consists of a single master station and multiple slave stations, which can lead to decreased communication efficiency in certain application scenarios. As IIoT (Industrial Internet of Things) continues to progress, there is a growing demand for new sophisticated applications that necessitate retrieving data from various industrial settings. As a result, multi-master station technology has been developed, enabling the retrieval of on-site data without disrupting the data collection process of the primary master station. However, most of these solutions require modifications to the original bus and the suspension of the original data collection process during installation. In order to maintain the integrity of the original bus system, this study introduces a Modbus multi-master technology in which the additional master employs a non-invasive listening approach to receive messages. It identifies request and response messages based on the protocol's function codes and message byte numbers, parses information, and shares the acquired data to IIoT applications. The technology was tested in an IIoT application in which a WirelessHART network node was converted into such a master, which uploads acquired data wirelessly to the IIoT application. The findings indicate that the new master successfully identified messages and exchanged data with precision