Shielding and routing bus cables

NOTICE

Flowing compensating currents due to the incorrect cable type, inadequate shielding, and/or the incorrect routing of bus cables.
Damage to property.
  • In the event of fluctuations in the ground potential, a compensating current may flow via the bilaterally connected shield that is also connected to the protective earth (PE). Make sure you always supply adequate equipotential bonding in accordance with the relevant IEC regulations.

The PROFIBUS fieldbus interface supports RS485 transmission technology. The cable type A specified by IEC 61158 for PROFIBUS is used as a shielded twisted pair cable.

Do the following to minimize electrical interference:

  • Tighten the retaining screws of connectors, modules and equipotential bonding cables below the guaranteed yield strength.
  • Tighten the retaining screws of connectors, modules and equipotential bonding cables to the tightening torque specified by the manufacturer.
  • Only use connectors with a metal housing or a metalized housing.
  • Connect the shielding in the connector over a wide surface area.
  • Apply the shielding of the bus cable on both ends.
  • Always route the signal and bus cables spatially separated from power cables (motor leads) and, whenever possible, in separate cable ducts.
  • Use metallic, grounded cable racks in industrial environments.
  • Route the signal cable and the corresponding equipotential bonding close to each other using the shortest possible route.
  • Avoid using connectors to extend bus cables.
  • Route the bus cables closely along existing grounding surfaces.