- SafetyBUS p
SafetyBUS p is a standard for safe field bus communication within
factory automation . It meets SIL level SIL 3 according to IEC 61508 andsafety category Cat. 4 of EN 954-1Originates
SafetyBUS p has been developed during the years 1995 to 1999 of the company
Pilz GmbH und Co. KG (Germany). It was the target to enable a field bus for safe communication in terms ofsafety in machinery . Since 1999 there is an installation basis of approx. 10.0000 applications with a total of about 150.000 safe field devices (per 2006).The technology of SafetyBUS p is administered already since 1999 by the user organization
Safety Network International e.V. (previously SafetyBUS p Club International e.V.). 70 companies world wide joint so far the user organization (per 2006) and contribute to the SafetyBUS p technology.Usage
The main use of SafetyBUS p is the communication of data with safety relevant content. SafetyBUS p is found where the data integrity and timely delivery of data is required for the protection against risks. In this respect risks may affect life or health, but as well the protection of valuables or machinery.
Typical applications are:
*Factory automation (e.g. automotive production, press lines)
* Transport systems (like cable cars, fun rides)In general all applications with safety requirements up to SIL 3 of IEC 61508 or Cat. 4 of EN 954-1 are possible, as long as the system possesses a safe state (this is not to be mistaken for a high availability system, which typically has no such state, but which is as well classified by SIL levels).
Technology
SafetyBUS p is based on the CAN field bus. Besides the
OSI layers 1 and 2 defined for CAN, SafetyBUS p adds mechanisms for safety in layers 2 and 7.Error detection mechanisms
For the detection of errors in transmission and within devices, SafetyBUS p uses the following mechanisms:
* Sequential numbering
* Watchdog
* Echo
* Sender and receiver ID
* Check of data integrity using CRCTechnical data
The key data defined by the technology of SafetyBUS p is as follows:
* Max 64 bus devices within one network
* Up to 4000 I/O signals per network,
* Transmission rate is 20 to 500 kBaud, depending on the physical size of the network
* Single network segments may be up to 3500 m in size
* Several network segments may be linked
* Guaranteed error reaction times of down to 20 ms may be achieved
* Suitable for applications according to SIL 3 of IEC 61508 and Cat. 4 of EN 954-1
* Optional power supply of the devices over the bus cable
* Network segments may be implemented using radio, fiber-optic or infra-red links.Devices
SafetyBUS p networks only contain safety devices. These devices are typically built using internal redundancy. The use of safety devices for safety applications usually requires the certification of the devices by notified bodies. These certify the devices according to applicable standards and norms. A functional certification is done by the user organization
Safety Network International e.V. .Organization
The user organization SafetyBUS p Club International e.V. exists since 1999 which is an association of users and manufacturers of SafetyBUS p devices. A national organization for Japan has been founded in 2000 and the US organization followed in 2001. In 2006 the organization changed its name to
Safety Network International e.V. .External links
Organizations:
* [http://www.safetybus.de Safety Network International e.V.]
* [http://www.safetybus.com Safety Network International USA (Regional organization for USA)]References:
* [http://www-pdv.fh-reutlingen.de/safety/ Portal about safety fieldbus communication - University Reutlingen, Germany]Literature
* Winfried Gräf: "Maschinensicherheit". Hüthig GmbH & Co. KG, Heidelberg 2004, ISBN 3-7785-2941-2
* Armin Schwarz und Matthias Brinkmann: "Praxis Profiline - SafetyBUS p - Volume D/J/E". Vogel Industrie Medien GmbH & Co. KG, Würzburg 2004, ISBN 3-8259-1919-6
* Armin Schwarz und Matthias Brinkmann: "Praxis Profiline - SafetyBUS p - Volume D/E". Vogel Industrie Medien GmbH & Co. KG, Würzburg 2002, ISBN 3-8259-1915-3
* EU machinery directive: "98/37/EG"
* Working paper BIA: "Prüfgrundsätzen für sichere Bussysteme"
* Reinert, D.; Schaefer, M.: "Sichere Bussysteme für die Automation". Hüthig, Heidelberg 2001. ISBN 3-7785-2797-5
Wikimedia Foundation. 2010.
