§3.3 – Installing

Rugged RJ-45 connector

Standard ‘best practice’ in cable installation and maintenance should be followed at all times. Here are a few installation tips that should be borne in mind:

  • Remember that the environment you are planning for may be dirty, dusty, electrically noisy and generally unfriendly to data transmissions and infrastructure components of all types.
  • Normal twisted pair cabling is suitable for PROFINET. TCP/IP has methods in place to resend telegrams when lost but the timing is not acceptable for industrial use! In other words, electrically noisy environments can easily interrupt your data flows and may cause control malfunctions. In these situations, always use Shielded Twisted Pair cabling.
  • Grounding at both ends is best. However, it’s not always applicable due to ground loops.
  • The need for shielding is independent of the protocol used. All Industrial Ethernets – and indeed fieldbuses – need protection in noisy environments. If you used shielded cable with DeviceNet or PROFIBUS, use shielded cable with PROFINET as well.
  • Use PROFINET-rated cable.
  • Always use rugged connectors too. Field installable RJ-45 types are available, as illustrated.

Read this installation guidelines before starting your project:

PROFINET Guideline for Cabling and Assembly