Tips when cabling an industrial communications system

 

 The cabling of an industrial communications system is reliable and cost-effective when correctly implemented. Avoid typical problems by observing the following rules:

 

 

  • Utilise components suitable for the communication system.
  • Use environmentally-friendly components
  • Additional loads ie continuous motion and torsion, must be specified by manufacturers in the data sheet.
  • Missing or incorrect terminating resistors often result in sporadic failures.
  • Avoid incorrect assignment: Incorrect pin numbering and conductor colours result in total failure.
  • Components that do not match one another, or a circuit that has been incorrectly connected up, result in unreliable contact points.
  • Carefully connect the shield: A 360°contact of the braided shield prevents sporadic failures for increased levels of EMC (electromagnetic compatibility) stress.
  • Suitable potential bonding must be implemented: Only a meshed system and a power supply in accordance with TN-S (earthing system) can avoid equalisation currents and therefore interference via the shield. Fibre-optic cables must be used if these conditions are not met.
  • Cabling drawings must be updated after any change so that faults can be located after a failure.

 

Take Note

  • The transmission medium, whether electrical or optical, is a critical part of any industrial communications system.
  • All components used in the transmission network must be chosen based on the environmental conditions to which they will be exposed.
  • The right component for all applications exists – it must just be specified and used.

 

Published as:

Classic fieldbus up to high-speed Ethernet: Communication plug connectors for industrial use

By Dipl-Wirt-Ing. B Horrmeyer, Phoenix Contact (Germany)

Electricity+Control: January 2012 (pgs 4 – 6).