GA75 contactors are designed for DC circuit switching. Arc suppression is more difficult in DC than in AC. To choose a contactor, it is necessary to know the current and voltage to be broken as well as the L/R time constant of the power circuit to be controlled. GA75 contactors are of the block type design. - Main poles: the contactors are fitted with arc chutes with permanent magnets specially designed for DC breaking. The three contactor paths are arranged in series via two supplied and fitted insulated connections (25 mm²). The GA75 are "single-pole" devices for which the connection polarities indicated next to the connection terminals must be respected. Furthermore, they are marked 1L1 for the positive terminal and 2T1 for the negative terminal.