Festo Rolls Out Suite of Safety Solutions for Pneumatic Systems

Compressed air has been used to provide motion to automated equipment since the birth of industrial automation. With motion comes danger, so the industry has developed safety protocols and standards to keep operators and maintenance safe. Any machine that uses compressed air must quickly exhaust all the air in the system so that motion will come to a complete stop. Typically, this exhaust function occurs at the main air supply dump valve: Festo has released new CIP safety valves that safely exhaust air at the source of motion.

Festo’s newest CIP modules prioritize safe pneumatic operation. Image used courtesy of Festo

Pneumatic Safety Solutions

In a typical application, a valve terminal would need to have its air supply delivered through a safety-rated quick exhaust valve. The wiring for the valve would then be controlled by the safety relay or safety PLC. While this architecture does function, it also requires extensive wiring and troubleshooting when things do not work. Festo has developed specific valves with safety in mind and added CIP safety communications right at the valve terminal.

A CPX system with VTUX valves and digital I/O. Image used courtesy of Festo

VTUX Valve Terminal

When a valve is triggered to spool over to position two, it takes time to get there, and typically, solenoids and springs are used to drive the valve position. In the event something goes wrong, you want to make sure the valve is in a safe position. Festo’s VTUX valve terminal uses negative overlap spools, which means the compressed air can still exhaust quickly even if the spool is in an intermittent position. Festo plans to continue adding safety features to this line of valves.

The CPX system with digital I/O. Image used courtesy of Festo

Common Industrial Protocol (CIP) Safety

CIP is a safety protocol control systems use to send safety signals over an Ethernet architecture. Festo has added CIP communication to its CPX product line with the VTSA-F-CB valves. This combination allows for up to three different safety zones on the same valve terminal. Each zone can be controlled by a PLC or safety relay. This configuration supports safety ratings up to Cat 3, Ple, and SIL3.

The CPX platform can also support I/O with the CPX-AP-A automation system, and both the VTUX valves and digital I/O can be combined on the same backplane. The CPX system can monitor each configured zone's supply air pressure and voltage to aid in writing the safety logic. This monitoring allows for a closed-loop system, and the safety controller will know whether the air has been completely exhausted. The CPX system can also run in a hybrid mode, facilitating remote and distributed I/O and valves.

Pneumatic Safety Solutions

Safety systems can be difficult to troubleshoot and design because of all the required choices and hard wiring. Using a system like the CPX-AP-A reduces a large portion of the wiring. Troubleshooting safety systems becomes easier when using industrial protocols such as CIP because of the baked-in diagnostic and monitoring features. By standardizing on a device such as the CPX-AP-A with VTUX valves, customers can ensure equipment will be safe and have fast integration.