Practical Industrial Data Networks:Design, Installation and ...

Index 419Network interface card (NIC), 241Ethernet problems:10/100 Mbps mismatch, 254bad packets, 252–3basic diagnostics, 250–1CRC errors, 253excessive broadcasting, 252faulty auto-negotiation, 253–4faulty CSMA/CD mechanism, 251full/half-duplex mismatch, 254improper packet distribution, 252incorrect media selection, 251jabbers, 251late collisions, 253misaligned frames, 253runts, 253too many nodes, 252wire hogging, 251Node communication problems:DeviceNet:excessive traffic, 180MACID/baud rate settings, 180node presence, 179Noise:DeviceNet, 179EIA-485, 61common mode, 62induced, 61reflections/ringing, 62–3shielding, 64–5unbalancing the line, 63–4Ethernet, 243–4identification with oscilloscope, 66industrial Ethernet, 237–8see also Electric noise; Electrical couplingof noiseOpen systems interconnection (OSI) model,6–7Operator interface, 3Optical time domain reflectometer (OTDR), 89,93–5, 242Oscilloscope, 66, 175data transfer, 67noise identification, 66ringing, 67Personal computer (PC)not listening for call, 119–20slave xx reported illegal data address, 120slave xx reported illegal data function, 120–3slave xx reported illegal data value, 120troubleshooting SA85 adapter card underWindows NT, 123Problems/solutions see TroubleshootingProfibus (PRO FIeld BUS), 2, 13–14application process/communicationrelationship, 190–1COMBI mode, 182communication model, 190communication objects, 191–2distributed peripheral (DP), 182Fieldbus message specification (FMS),182, 187–8overview, 181–3PA protocol, 182–3performance, 192protocol stack, 183application layer, 187data link (layer 2), 184–6Fieldbus management layer (FMA 7), 189FMS, 187–8lower layer interface (LLI), 188–9physical layer (layer 1), 183–4system operation:configuration, 192–3DPMI/DP-slaves data transfer, 194FMS/DP stations mixed operation, 195safety/protection of stations, 194–5synchronization/freeze modes, 194troubleshooting, 195tips, 198–9tools, 195–8Programmable logic controllers (PLCs), 3–4Protocols, 2, 7–8see also StandardsRadio/wireless communications:characteristics of VHF/UHF, 281–2components, 278antenna, 278antenna support structure, 279cabling, 279receiver, 278transmitter, 278implementing a link, 289fade margin, 295–6miscellaneous considerations, 296–7path profile, 289–92RF path loss calculations, 292–3signal to noise ratio/SINAD, 294–5summary of calculations, 296transmitter power/receiver sensitivity, 293–4intermodulation/prevention, 287–9modems, 282–5channel date rate, 287features, 286–7host data rate/format, 286minimum frequency signal level, 287modes, 285–6