The restrike time for re-light up of an arc discharge lamp may be decreased by including at least one refractory bimetallic start up electrode that provides a shorter arc path intermediate the main arc path in a cool state, but when heated withdraws to have a relatively longer arc path. The longer arc path in the hot state results in a relatively higher path impedance that can be used by itself or in combination with a supplemental impedance device to extinguish the starting arc in favor of the main arc. The withdrawn bimetallic starting electrode then does not interfere with the main arc function.