SCS open link interface now TÜV certified up to SIL3

Hengstler, a supplier of encoders for motion feedback control, announces that SCS open link, the open motor feedback interface, has now been certified by TÜV Rheinland for use in applications up to SIL3 (Safety Integrity Level).

The single-cable solution meets all functional safety requirements according to IEC 61508-2: 2010 and IEC 61784-3: 2017 (extracts). 

SCS open link is an interface for communication between the drive and motor, using one cable with either four wires or two wires and high performance software with high safety level.  

SCS open link was designed for high performance motion control with safety communication through black channel concept.  

The interface was also designed to be used in Industry 4.0 applications to carry IoT sensor data in a secure transmission.

With this certification, TÜV Rheinland has confirmed that the SCS open link interface can be used in all machines and systems of the SIL1-3 categories. This is an important decision criterion for motor feedback, automation and high performance motion control because the functional safety of plant components are becoming increasingly important due to the increasing complexity of the overall systems. 

SCS open link interface allows the use of a standard controller without special hardware requirements saving costs and simplifying the design process.

SCS open link is suitable for condition monitoring and predictive maintenance applications, which are increasingly in demand in the industry.  

“Machine builders, drive manufacturers, and motor OEMs can connect vibration, temperature, or other IoT sensors to monitor health of their machines using the SCS open link interface”, reports Johann Buecher, Director of Encoder Strategy for Hengstler. “With SCS open link and our encoders, the user always has control over the status of his plant. Combined with our Advanced Analytics modules, this creates a value chain that is of great interest to machine builders and service providers”.

The data protocol of SCS open link not only meets the SIL3 requirements, but also those of performance level e (PLe), category 3 (according to EN ISO 13849). 

When used together with a safety rated encoder, such as the Hengstler ACURO  AD -Series product line, engineers can easily design for applications requiring functional safety. 

These encoders were developed for use with the interface, and feature redundant signals that are transmitted synchronously via  a single cable, fulfilling the requirements of a black channel. If any failure occurs at the encoder or during the transmission, the higher-level safety evaluation controller will detect all possible failure modes and keep the system in a safe operational state. 

In addition, the encoders provide diagnostics tools that allow the controller to take action to safely continue to operate the motor connected to the encoder in the event of a transmission error.