Nowadays, functional safety can be implemented over the bus shifting from safety in hard-wired relays to safety performed in logic. PROFIsafe is an additional software layer that provides functional safety over the bus in PROFINET networks. PROFIsafe ensures the integrity of failsafe signals transmitted between safety devices and a safety controller meeting the relevant safety standards for industrial
networks (up to SIL3 according to IEC 61508 / IEC 62061, or Category 4 according to EN 954-1, or PL “e” according to ISO 13849-1). PROFIsafe is also safety certified for wireless transmission channels such as WLAN and Bluetooth. Therefore, PROFINET users can utilize PROFIsafe for functional safety and transmit safety messages over their standard network, which can include WLAN or Bluetooth connections.
PROFIsafe ensures that the network won’t fail in an unsafe manner, regardless of the physical layer. If the physical layer is not reliable, then the data might be continuously lost or corrupted. In that case, PROFIsafe will detect the errors, and the machines or devices involved will go into a predefined safe state while operations stop. But, constant stops and interruptions are unacceptable in industrial environments. For that reason, ensuring a reliable wireless connection should be the first step when implementing safety over wireless. We recommend performing wireless site surveys, exploring multiple wireless topology configurations, implementing industrial wireless access points, and any necessary steps to ensure reliable wireless connections. The articles below are two case studies that feature PROFINET applications. In both case studies, users implemented wireless networks for their standard and safety PROFINET data. Click on their title if you would like to read the full case study.
Case Studies: PROFIsafe over Wireless
In the twelve years since the installation of PROFIsafe over wireless at the Sacre Coeur on Montmatre, not a single failure of communication or any actuation of the safety function by the radio link has occurred. A look back and a look forward.
To watch a Fori Automation Automated Guided Vehicle (AGV) operate is to witness an engineering marvel. The AGVs are steadily moving up to two feet per second across the floor of an aerospace manufacturing facility. One carries a 30-ton, 60-foot-long jet wing frame for a commercial jet aircraft to its assembly point.
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