Within just 6 months Sensor-Technik Wiedemann (STW) has achieved 6 safety approvals for the current generation of 32 bit mobile control units in accordance with the machine safety standards EN 61506, SIL2, EN62061 SIL C2 and EN ISO 13849 PLd.
The first approval for the unique memory protection mechanism for the electronic control unit ESX®-3XL was received on the 19th of September 2013. That approval means that the application software can access both standard and safety functions in parallel.
Building on that success, STW (www.stw-technic.com)
In February 2014 STW received the SIL2/PLd certificate for the ESX-3XM electronic control unit. With that, both 32 bit safety controllers, the ESX®-3XL and ESX®-3XM offer a certified independence between safety and standard functionality. This means that both safety and standard I/Os can be controlled on one control unit, and the safety functionality is protected from the interference. With this approach, there are literally millions of feasible control unit variants available through the inclusion of approved expansion boards. Additional I/O, RS232/RS485, CAN, Ethernet and USB functionality can all be added without compromising the safety functionality or certification.
Currently there are 14 expansion boards (EBs), which can be used for independent standard functions. The first Safety Expansion Board (according to DIN IEC 61508 and EN ISO 13849) is in development. This can be used in the ESX®-3XL and ESX®-3XM basis for SIL 2/PL d functions. The Safety EB offers, with a redundant mainboard channel, the following additional safe I/O functionality:
• 16 safe digital high-Side outputs,
• 16 safe digital or voltage inputs, and,
• 2 safe analog current inputs.
When combined with the basic I/O channels of the ESX®-3XL that adds up to 84 safe I/O channels within one control unit.
On the 14th of March 2014 the first certificate for CODESYS Safety SIL 2 Runtime System for the ESX®-3XL was issued. STW was thereby the first mobile controller manufacturer to offer a certified Runtime System for application developers. For the first time, developers could develop a safety related IEC-61131 application on a mobile controller.
Mr. Wolfgang Wiedemann, Managing Director of Sensor-Technik Wiedemann GmbH, commented that "Being able to offer holistic, long term system solutions for the control of mobile machines, and having the unique safety concept confirmed and approved by the TÜV Süd is very satisfying, and I’m very pleased to have achieved these milestones".
STW (www.stw-technic.com) is an award-winning provider of a full spectrum of freely programmable controllers, I/O modules, pressure sensors and telematics to a wide range of industries such as mining, construction, agriculture and oil and gas. STW controllers, I/O modules and Telematics units have attained a leading role in these industries due to their rigorous testing, high quality German engineering and unmatched flexibility. All of STW’s products are mobile off-highway rated. STW is also in the forefront of developing and prototyping hybrid drive technologies – generators and motors – for mobile applications. Information on STW's functional safety controllers are available at: http://www.stw-