SafetyBUS p
SafetyBUS p is a standard for fail-safe fieldbus communication in automation technology . It fulfills SIL 3 of IEC 61508 as well as safety category Cat. 4 of EN 954-1 and Performance Level "e" (Cat.4) of the successor standard EN ISO 13849 .
Emergence
SafetyBUS p was developed between 1995 and 1999 by Pilz GmbH & Co. KG . The aim was to provide a fieldbus for the communication of data in terms of machine safety.
Since 1999, the SafetyBUS p technology has been administered by the user organization Safety Network International eV (previously SafetyBUS p Club International eV ), in which the members are working on the further development of SafetyBUS p.
commitment
The main use of SafetyBUS p is to communicate data with safety-relevant content. SafetyBUS p is used wherever the time and content consistency of communicated data is required to protect against hazards. The dangers can be a threat to life and limb, but also the protection of assets.
Typical areas of application are:
- Factory automation (e.g. automobile production, presses)
- Transport technology (e.g. cable cars, rides)
SafetyBUS p can be used for applications with safety requirements up to SIL 3 of IEC 61508 or Cat. 4 of EN ISO 13849-1 .
technology
SafetyBUS p is technologically based on the CAN fieldbus system . In addition to the OSI layers 1 and 2 already defined in CAN for bit transmission and security, SafetyBUS p also has additional mechanisms for securing transmission in layers 2 and 7.
Failure mechanisms
The following mechanisms are used with SafetyBUS p to detect transmission and device errors:
- Consecutive numbers
- Time expectation
- echo
- Identifier for sender and receiver
- Data backup (CRC)
Technical specifications
The framework data of SafetyBUS p determined by the technology are as follows:
- A maximum of 64 bus participants per network
- Up to 4000 I / O points per network
- Transmission rates 20 to 500 kbaud, depending on the network expansion
- Individual network segments can extend up to 3500 m.
- Several network segments can be linked
- Guaranteed error response times of up to 20 ms can be achieved
- Suitable for applications according to SIL 3 of IEC 61508 and Cat. 4 of EN ISO 13849
- Optional power supply for the devices via the bus cable
- Partial networks can be implemented using radio technology, fiber optic cables and infrared connections.
equipment
Safety-related devices are used exclusively in SafetyBUS p networks. These are usually built internally with multiple channels. The safety-related use of the devices normally requires certification of safety by authorized test laboratories. They check the devices in accordance with the applicable standards and regulations. A functional test is carried out by the user organization Safety Network International eV
organization
The user organization Safety Bus p Club International eV , in which manufacturers and users of SafetyBUS p have come together, has existed since 1999 . The organization was renamed Safety Network International eV in 2006. In addition to the international organization, there are two other regional organizations: Japan, founded in 2000, and the USA, founded in 2001. The organization continues to develop the system, so SafetyNET p could be made available as a successor.
literature
- Winfried Gräf: Machine safety . Hüthig, Heidelberg 2004, ISBN 3-7785-2941-2 .
- Armin Schwarz, Matthias Brinkmann: Praxis Profiline - SafetyBUS p - Volume D / J / E . Vogel Industrie Medien, Würzburg 2004, ISBN 3-8259-1919-6 .
- Armin Schwarz and Matthias Brinkmann: Praxis Profiline - SafetyBUS p - Volume D / E . Vogel Industrie Medien, Würzburg 2002, ISBN 3-8259-1915-3 .
- IFA Report 2/2017: Functional safety of machine controls - application of DIN EN ISO 13849
- BG ETEM, test principle GS-ET-26: Bus systems for the transmission of safety-relevant messages
- EU machinery directive: 98/37 / EG
- D. Reinert, M. Schaefer: Safe bus systems for automation . Hüthig, Heidelberg 2001, ISBN 3-7785-2797-5 .