ITU-T L.1203 PDF

The scope of this Recommendation is to define common practice for identification of cabling or parts of the DC electric distribution inside buildings and rooms and inside telecom, ICT and facilities equipment (power plant, cooling, building access, monitoring, etc.).

This applies to 400 VDC cabling for telecom, ICT equipment and environment equipment using interface defined in [b-EN 300 132-3-1] or [ITU-T L.1200] and avoids confusion between the DC colour and marking of up to 400 VDC distribution and the other power interfaces identification: −48 VDC distribution for A interface, AC and uninterrupted AC given by inverters or UPS used in the building.

The Recommendation defines:

– requirements for the colour and identification of separate wires used in DC distribution systems and installations and as much as possible inside equipment between A or P interface and end use; – marking and identification of DC multiwire cables, connectors and any associated equipment for DC power distribution;

– marking identification for sub-distribution boards and interconnection boxes.

For DC wires in multiwire cables, recommendations are given for harmonization with separate wire requirements.

Recommendations are given on other distribution items (wires, cables and interconnection items) including the functional earthing and bonding arrangement for distribution outside and inside equipment to avoid any confusion with DC distribution identification of this Recommendation.