The purpose of this document is to collect information and report experience in order to make recommendations for the standardization of voltage levels and related aspects (power quality, EMC, measurement …) for LVDC systems (systems with voltage level lower than 1 500 V d.c.).

Rationale for the proposed voltage values are given. Variation of parameters for the voltage (power quality) and recommendation for their boundaries are defined. Nevertheless, some of the technical items are not exhaustively explained in this document and some gaps are identified for future work.

Attention is paid to the definition of DC voltage.

Systems in which a unipolar voltage is interrupted periodically for certain purposes, e.g. pulse voltage, are not considered.

Traction systems are excluded from this document.