Inclination sensors

General informationNotes and explanationsGeneral introductionThe structure of the networkThe ISO 11898 standard assumes a line structure of the CAN network. Inaddition the CAN H and CAN L cables must be provided with a 120 Ω terminatingresistor on each end.Node 1Node nGeneralstructure of aCAN network.CAN_H120CAN Bus Line120CAN_LIdeally, no spur should lead to the bus participants (node 1... node n) becausedepending on the total cable length and the transmission time, reflectionsmay occur on the bus. However, in practice this requirement often cannot beimplemented. In order to avoid that the spurs to a bus participant (e.g. to anI/O module) cause system errors they should not exceed a certain length.Spurs up to a length of 2 m are considered to pose no problem. The sum ofall spurs in the whole system should not exceed 30 m. In any case a networkdesign should be examined under real conditions (field test) in practice.The length of the bus cable depends on the characteristics of the bus connection(cable, connector), the cable resistance and the necessary transmissionrate (baud rate). As described above, the length of the spurs must alsobe considered for the network design. Simplified, the following dependencebetween bus length and baud rate can be assumed:The maximumdata transmissionrate depends onthe length of thebus cable.baud rate [Kbits/s]10005002001005020105010 50 100 200 100010000bus length [m]Visit our website: www.ifm.com14