study*

Thread Content

The marking of explosion-proof electrical equipment includes the type, rating, category, and group; it shall be placed in a prominent position on the external main body of the equipment, and shall be clearly visible after the equipment is installed. The correct meaning of the label “Er dⅢB T3 Gb” is (). 　　A. Increased safety type “d”, with a protection rating of Gb; used for explosion-proof electrical equipment in explosive gas environments of category T3, group IIB. B. Encased type “d”, with a protection rating of T3; used for explosion-proof electrical equipment in explosive gas environments of category Gb, group IIB. C. Flameproof type “d”, with a protection rating of Gb; used for explosion-proof electrical equipment in explosive gas environments of category IIB, group T3. D. Intrinsic safety type “d”, with a protection rating of II B; used for explosion-proof electrical equipment in explosive gas environments of category T3, group Gb