Your Comprehensive Guide to Wireless Functional Safety Applications

Your Comprehensive Guide to Wireless Functional Safety Applications

The last 15 years have seen unprecedented growth in industrial connectivity. This has been driven by increasing demand for system performance while being supplied by consumer and IT communication technologies that brought costs down. At home and in the office, we have built up an expectation of how well wireless should perform. And that has led wireless communications to become the first-choice connection method at home and for many communications at the office. Wireless solutions are becoming more common in industrial environments and for good reason. These are some of the many ways that wireless industrial communications are enabling more effective production:

∙ Modular and flexible plant design

∙ Remote process instrumentation

∙ Data collection on legacy equipment

∙ Automated guided vehicles (AGV)

∙ Automated mobile robots (AMR)

∙ Independent cart technology (ICT)

∙ Automated storage and retrieval systems (ASRS)

∙ Predictive analytics for moving machinery

∙ Reducing cabling for hygienic design

With each new advance in technology, wireless communications achieve better performance, so there are likely to be even more cases that can be enabled. There are some cultural and technical barriers that must be addressed at companies adopting wireless communications within operational environments, such as achieving employee safety. 

What about safety?

Safety is particularly important for mobile equipment, moving machinery, reconfigurable plants, and anywhere where humans are in immediate proximity to dangerous items in the industrial control system. These applications present unique challenges for industrial communications, such as how to communicate industrial information wirelessly and how to keep employees safe while interacting with mobile machinery. Wireless communications have been making steady improvements and many applications can be accomplished today with functional safety as part of the design.

How can safety work over wireless? First, it makes sense to consider functional safety requirements generally, and how those work over industrial communications. There are many standards related to functional safety in different contexts. The common themes for industrial control systems are:

∙ Reduce the risk of a component failure or system failure

∙ Quantify the risk of failure after reductions are in place

∙ Detect when failures occur

∙ Ensure that failures always lead to a safe state

This is done by using good design practices, applying oversized components, performing statistical analysis of failure modes, and running diagnostics regularly, among other techniques. Modern standards for safety system design, such as IEC 61508 and IEC 62061, specify how to apply those techniques to electronics in the system, while IEC 13849 adds in electromechanical systems. How do those good principles apply to something like networked communications, especially wirelessly?

Click here to download the full application guide, which addresses how to apply functional safety communication protocols like CIP Safety over wireless/cableless communication networks. The advantages for wireless networks are discussed, followed by principles for functional safety. Industrial communications, particularly EtherNet/IP™, are reviewed in both wired and wireless contexts. The diagnostic capabilities of CIP Safety are introduced, followed by the procedures for deploying a successful wireless network using CIP Safety.