Motivation

The electromagnetic interference experienced by telecommunications networks due to power systems and electrified railway systems has been studied by ITU and documented in the nine volumes of the Directives and in a number of Recommendations. There is a need to maintain these documents and to ensure good coordination between them.

This Question impacts climate change issues by ensuring that the adequate resistibility requirements for equipment and protective measures for installations reduce the amount of equipment and installation damage. By reducing damages less fossils fuels are burnt (personnel do not have to drive to a site to repair equipment) and less manufacturing is required (less replacement equipment is needed).

The following Recommendations and Directives, in force at the time of approval of this Question, fall under its responsibility:

• K.5, K.6, K.7, K.8, K.9, K.13, K14, K.19, K.26, (K.54, K.57,) K.68, and the Directives, except Volume VIII.

Question

Study items to be considered include, but are not limited to:

• Interference caused by power and traction systems to telecommunication systems.
  • Interference to telecommunication transmission systems other than POTS, e.g. limits for ISDN and xDSL;
  • Interference to telecommunication systems by the emergence of harmonics flowing on power systems.
• Earth Potential Rise (EPR) when the HV, MV and LV earthing systems are connected.
  • Magnitude of transferred voltage caused by phase to earth short circuit of MV network with directly earthed neutral and double earth fault of network with not directly earthed neutral
  • Method (measurement) for identifying the earthing resistance of MV/LV transformer station relevant to transferred potential in urban area.
• Transients occurring on LV supply networks as sources of interference to broad band technologies (in collaboration with Q. 8/5).

Tasks

Tasks include, but are not limited to:

• A new Recommendation on interference to telecommunications transmission systems other than POTS, e.g. limits for ISDN and xDSL;
• A new Recommendation on Earth Potential Rise (EPR) and transferred EPR; K.hvps
• Revision of Volume V of the Directives with regard to:
  • Earth Potential Rise (EPR) when the HV, MV and LV earthing systems are connected directly or indirectly in both normal and faulty conditions;
  • Emergence of harmonics on power plant.
• Maintenance and enhancement of some other Volumes of the Directives;
• Maintenance and enhancement of the relevant Recommendations.

NOTE: The revision of the Directives should be done in collaboration with CIGRE and UIC.

An up-to-date status of work under this Question is contained in the SG 5 Work Program (use URL as shown in the table below).

Relationships

Recommendations:

• K-series

Questions:

• 8, 11, 12 and 13/5

Study Groups:

• ITU-T SG 15
• ITU-D SG 2

Standardization bodies:

• CIGRE, CIRED, UIC