UL 60079-6-2020 pdf free download.Explosive atmospheres – Part 6: Equipment protection by liquid immersion “o”.
3.5 maximum permissible protective liquid level maximum level that the protective liquid can attain in normal service, taking into account the effects of expansion from the worst-case filling condition specified by the manufacturer to the condition of full load at maximum ambient temperature for which the equipment is designed 3.6 minimum permissible protective liquid level minimum level that the protective liquid can attain in normal service taking into account the effects of contraction from the worst-case filling condition to the condition of de-energization at minimum ambient temperature
3.7 disconnector mechanical switching device which provides, in the open position, an isolating distance in accordance with specified requirements Note 1 to entry: A disconnector is capable of opening and closing a circuit when either negligible current is broken or made, or when no significant change in the voltage across the terminals of each of the poles of the disconnector occurs. It is also capable of carrying currents under normal circuit conditions and carrying for a specified time currents under abnormal conditions such as those of short circuit. [SOURCE: IEC 60050-441:1984, 441-14-05]
3.8 switching device device designed to make or break the current in one or more electric circuits [SOURCE: IEC 60050-441:1984, 441-14-01] 3.9 safety device device intended for use inside or outside explosive atmospheres but required for or contributing to the safe functioning of equipment and protective systems with respect to the risks of explosion 3.10 tap selector device designed to carry, but not to make or break current, used in conjunction with a diverter switch to select tapping connections [SOURCE: IEC 60050-421:1990, 421-11-02]
4 Constructional requirements
4.1 General For Type of Protection “liquid immersion “o”, the Ex Equipment or parts of the Ex Equipment are immersed in a protective liquid in such a way that an explosive gas atmosphere, which may be above the liquid or outside the enclosure, cannot be ignited. The Ex Equipment is constructed to ensure that the necessary amount of protective liquid is present. Dependent on the intended Equipment Protection Level, this is achieved by monitoring device(s), indicator (s) or a level control safety device with automatic switch off.UL 60079-6 pdf download.