A connector that has a phase terminal, an earth terminal and an insulating body inside which the phase terminal is housed and on the outside of which the earth terminal is coupled. According to some embodiments the insulating body has at least one opening extending axially from an end of the insulating body. The earth terminal is formed at least in part by an elastic body surrounding the insulating body extending along the opening, said elastic body being configured for being deformed against the inside of an earth terminal of a safety valve when the insulating body expands radially outwards, assuring electrical continuity between the elastic body and the earth terminal of the safety valve.