Product catalog - TURCK

FOUNDATION fieldbusBasicsFOUNDATION fieldbus – Bus physicsWith the publication of the internationalstandard IEC 61158-2 in October 1994,a suitable transmission technology wasdetermined and internationally specifi edfor the application areas of FOUNDA-TION fi eldbus and PROFIBUS-PA. Thiswas later integrated into the Europeanstandards as EN 61158-2.bus voltage9...32 Vfieldbus data signal0,75...1,0 V SSBoth systems comply with IEC 61158-2and operate on the voltage mode with atransmission speed of 31.25 kBit/s. In thisway the data packages are modulatedonto the supply voltage for the fi eldbusstation and transmitted via a shielded twowirecable (see Fig. 1).These bus physics offer a decisiveadvantage: fi eldbus communication andpower supply of the bus station can beimplemented using a single cable. Thesebus physics lead to enhanced operationalsafety and lower costs compared with theconventional fi eldbus solution used up tothis point with its additional wiring effort.Fig. 1 Transmission of data packages to IEC 61158-2tCharacteristic features of the IEC 61158-2 transmission physicsData transmissionTransmission speedData securityCableRemote supply of the stationsProtection classesTopologyNumber of stationsRepeaterdigital, bit synchronous, Manchester coding31.25 kBit/s, voltage modepreamble, fault protected start and end delimitershielded and twisted 2-wire cableoptionally via signal cablesintrinsically safe (Ex ia/ib or Ex nL), increased safe (Ex e or Ex nA) andexplosion protected (EEx d/m/p/q)spur and tree topologies; also in combinationup to 32 stations per cable segmentcan be extended with a maximum of 4 repeaters6 /0309 Hans Turck GmbH & Co.KG • Witzlebenstraße 7 • 45472 Mülheim/Ruhr • Germany • Tel. +49 (0)208 4952-0 • Fax +49 (0)208 4952-264 • more@turck.com • www.turck.com