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Case Studies

Growing demand for Integrated Safety Networks using PROFIsafe


UK-based Fortress Interlocks is a manufacturer of premium safety interlock systems for in-dustrial applications. These are used to help prevent a machine from harming its operator or damaging itself. The interlocks stop the machine whenever certain states occur such as the opening of a door or the push of a button. Fortress Interlock’s customers come from many lines of business such as power generation, steel making, automotive manufacturing, food and beverage processing, materials recycling and construction. 


Lately, Fortress Interlocks has seen an increasing demand for interlock solutions which are compatible with PROFIsafe – the safety standard of PI which is often used within PROFINET networks – and wanted to be able to offer an integrated safety solution for PROFINET and PPROFIsafe.


Fortress Interlocks decided to turn to HMS which had such an integrated safety solution al-ready in place which would fit very well with Interlock´s modular product approach (figure to the left). They implemented an HMS integrated safety module which controls the safe I/O signals - using the black channel principle - and works together with a HMS communication module to handle the unsafe network communication (figure to the right).  

Developing a safety solution can be a time-consuming process since the certification re-quirements are rigorous, but with the HMS components, Fortress Interlocks could get a solu-tion in place relatively quickly: “We wanted to be able to offer a PROFINET-PROFIsafe solu-tion quickly which is why we turned to HMS,” says Rob Johnson, Senior Electronics Engineer at Fortress Interlocks. The cooperation with HMS included a TÜV precertification and al-lowed Fortress Interlocks to move into a new technical area quickly with a lower capital in-vestment. 

With the capability to offer safe communication with PROFINET, Fortress Interlocks now has a competitive edge on the growing Industrial Ethernet based market.

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