Case Studies

Project
In the food industry alongside perfect production control, efficiency, flexibility and safety are the
increasingly important factors. A potato washing machine with numerous intermediate stations had to be installed by a system house (Schulz Systemtechnik): everything from the power supply to the motor controllers and visualisation to the complete electrical system, including lighting and telephones.
The plant is operated 365 days a year, 24 hours a day in a 4-shift working cycle. As the potatoes are supplied for further processing into potato chips and crisps, without any interruptions; high levels of reliability, safeguards against failure and availability were the top priorities.

Solution
Different protocols and more than 200 participants like operating panels, drive and I/O systems made networking the potato washing machine a challenge. PROFINET, Ethernet and an internal in-house network run over the same cabling. In addition, visualisation needed to be possible at all locations.
To avoid network failures, the use of active devices with efficient filter mechanisms was called for in order to reduce the broadcast traffic. Managed switches (Weidmüller) of the last generation with their additional features and individual setting options were selected to provide the reliable communications between the machine segments and the plant parts as well as the higher-level office networks.

Conclusion
The responsible engineer at Schulz Systemtechnik states his experiences:
“PROFINET means that we have more freedom and flexibility when building structured networks and managed switches are the ideal solution for use in PROFINET networks. They provide a simple way of building a complex network configuration."