EVS-EN 60079-6:2015+A1:2024

This part of IEC 60079 specifies the requirements for the design, construction, testing and marking of Ex Equipment and Ex Components with type of protection liquid immersion “o” intended for use in explosive gas atmospheres.
Ex Equipment and Ex Components of type of protection liquid immersion “o” are either:
•  Level of Protection “ob” (EPL “Mb” or “Gb”)
•  Level of Protection “oc” (EPL “Gc”)
For Level of Protection “ob”, this standard applies where the rated voltage does not exceed 11 kV r.m.s. a.c. or d.c.
For Level of Protection “oc”, this standard applies where the rated voltage does not exceed 15 kV r.m.s. a.c. or d.c.
Additionally, for Level of Protection "oc", Annex D applies where the rated voltage exceeds 15 kV AC RMS or DC and up to 245 kV AC RMS or DC.
Annex D applies specifically to liquid immersed transformers and reactors, and other liquid immersed equipment such as swivels for off-shore platforms, power regulators, tap changers and earthing/switching resistors.
This standard supplements and modifies the general requirements of IEC 60079-0. Where a requirement of this standard conflicts with a requirement of IEC 60079-0, the requirement of this standard takes precedence.