Abstract: A two-part separable inductive coupler is provided in one part with a current-limiting reactor whose control winding is energized by control means in response to the formation of a magnetic circuit between primary and secondary windings incorporated in said one part and the other said part respectively. Said control means may comprise a rectifier connected across said primary winding and is arranged to saturate the reactor when the coupler parts are connected and leave the reactor unsaturated when the parts are separated, so as to limit the primary current.