Fieldbus users increasingly demand – besides field device diagnosis – also permanent moni-toring of PROFIBUS networks to ensure best possible operational quality and plant availability. Bus monitoring enables plant operators to recognize and remove malfunctions or irregularities of the bus data traffic in time. In the past, the lack of suitable and cost effective solu-tions has limited the number of implementations. This has changed now!
Evonik Goldschmidt in Essen (Germany), part of the Chemicals Business Area of Evonik Industries AG, uses a web-based, combined bus monitoring and Ethernet-PROFIBUS inter-facing solution in three installations with various PROFIBUS masters. The maintenance staff highly benefits from this application in daily use.
It did not take long until the monitoring solution provided the first valuable results and in-sights. “When PROFIBUS is up and running, it keeps running,“ says Dirk Deckers, who works in the Electrical Engineering and Process Control Service Department. Although the bus seemed to be functioning perfectly, for the first time ever we realized all the things going on on the bus, and we immediately identified scores of irregularities. “For the most part, the malfunctions could be removed immediately by small re-configurations of channel diagnoses.
This monitoring solution, when used on PROFIBUS, provides additional functions to the user which did not exist before. Examples are the automatic email alert function to inform the op-erator immediately if there are any problems or not; or special diagnosis functions to narrow the troubleshooting extremely down by informing the user on whether there are problems with the bus or if it’s a case of a failed channel.
Plant equipment is subjected to constant optimization processes with changes or extensions. Incorrectly attached bus connectors, for example, can turn the DP line into an antenna and cause (partial) downtime. With permanent monitoring of the network, it is easy to track what kind of work has been done when and at which spot – which means that failures can be lo-cated much more quickly. In a worst-case scenario, an engineer can react very quickly by using the web interface from anywhere for immediate diagnosis of the network.
“This solution has reduced reaction times extremely. A few hours of batch-plant downtime easily amount to a loss of EUR 50,000 or more, depending on the product,“ underlines Deckers. And: “Everything web-based facilitates our work. We don’t have to install software or do any updates.”
“Bus monitoring” can be considered as a very helpful cross-industry fieldbus application. PROFIBUS, because of its openess, enables this application and provides remarkable support to all users.The above solution, besides its basic function to interface Ethernet and PROFIBUS, allows with little effort and without special know-how, to identify problems at a very early stage and to locate causes of malfunctions extremely quickly. The solution contributes to minimizing unscheduled downtime, increasing availability, and saving a lot of time and money.
(This article has bee contributed by Trebing + Himstedt).