Powerful SX6 safety module for STOBER drive controllers

(See STOBER at Machine Building North, 10 April 2025, on stand 55)

STOBER's 6th generation offers powerful drive controllers for high-efficiency multi-axis applications. It includes the compact SC6 stand-alone device as well as the SI6, which eliminates the need for redundant power supply units thanks to a central supply module and was designed for controller-based applications in multi-axis drive systems.

The SX6 safety module, a brand-new addition to the range, can be equipped as an option for both series. It is suitable for safety-related applications up to SIL 3, PL e (category 4) in accordance with DIN 61800-5-2 or DIN EN ISO 13849-1.

The SX6 enables the conventional Safe Torque Off (STO), Safe Stop 1 (SS1) and Safe Stop 2 (SS2) stop functions. A highlight is that the STO safety function can also be activated individually for each axis on multi-axis controllers. It also features Safely-Limited Speed (SLS) and Safe Speed Range (SSR), Safe Direction (SDI), Safely-Limited Increment (SLI) and Safe Operating Stop (SOS).

STOBER developed the safety module in close collaboration with Pilz. In order to continue increasing the productivity and availability of the machine, the drive specialist has expanded the monitoring mechanisms of the safety functions beyond basic standardised requirements.

Due to position-based limit value monitoring and the predictive hiding of interference signals, the intended limit values can be approached with a minimal interference distance. SX6 tests the integrated components upon every device start-up, after every STO and during operation. As a result, cyclical function tests of safety functions that are subject to documentation at the end customer's location are unnecessary.

STOBER has also revised the switch-off channels of the STO and SS1 stop functions. At five and six milliseconds, respectively, they have become significantly faster. These short-worst case response times, minimised safety distances and, above all, fast restoration of availability significantly reduce downtimes and thus increase system availability. SX6 is controlled via EtherCAT. This is based on the secure Safety-over-EtherCAT protocol (Fail Safe over EtherCAT, FSoE).

o special motors, encoders, cables or standstill or speed monitors are needed to operate the safety module. When servicing is required, companies can use an SD card as a data storage device to transfer an existing safety configuration to other controllers quickly and easily.