Today fieldbus systems are a widely accepted standard in the field of process engineering. Several years ago fieldbus technology was mostly confined to the domain of manufacturing industry but now more and more branches, e.g. process automation, building automation and sewage plant automation, use fieldbus technology.
Fieldbus systems are the backbone of communication. In the lower levels of the automation hierarchy they render distributed automation systems possible. Distribution expands the working capacity and flexibility of a plant; thus improving the solution of given automation problems.
As installation of fieldbus networks is concernend the higher complexity of digital communication systems requires larger efforts in comparison to analogue data transmission. A simple current and voltage measuring of the process data is not a sufficient technique anymore. For this purpose several diagnostic measurement tools were developed which can be classified into following groups:
Cable Testers: Cable testers are mobile and locally used devices that diagnose the electrical characteristics of fieldbus systems. They analyze network faults like short circuits or missing bus terminators and evaluate the signal quality of connected devices.
They support the errror detection during the commisioning phase of the system and in case of network problems during operation.
The isPA Bustester of ifak system GmbH is such a measurement tool for the process engineering (ProfibusPA) field.
Bus Monitor: Digital communication uses defined communication protocols for the data transmission, related to the OSI-layer-model. Protocol decoders, the so called bus monitor, can supervise the data communication. They allow continuous recording and and interpretation of the data stream within a fieldbus system. Bus monitors are employed in case of network problems during operation as well as for long term supervision of a network.
ifak system offers a modular fieldbus monitor with different software options for Profibus (PA and DP) and Foundation Fieldbus standards.
