voltage which does not exceed 50 V AC r.m.s. between conductors, or between any conductor and earth
Note 1 to entry: The voltage limit should not be exceeded, either at full load or no load, but it is assumed, for the purpose of this definition, that any transformer or converter is operated at its rated supply voltage.
Note 2 to entry: Information about protection by extra-low voltage is given in IEC 60364-4-41.
Source: IEC 61892-6, Mobile and fixed offshore units – Electrical installations – Part 6: Installation, Third Edition, December 2013. Global Standards