A system ("S") adapted for driving or propelling a vehicle powered by a battery set along a roadway, comprising "a" a plurality of roadway sections (2a1, 2a2) subdividing the roadway, wherein said roadway and each one of these roadway sections comprise at least one elongated canalization, said canalization comprising at least one groove having at least one electric conductor (4a, 4b) introduced therein and being connectable over a switch to one or more vehicle-external electric power sources ("III"), including a vehicle-external electric station ("s1"), so as thereby to be able to charge said battery set belonging to said vehicle but primarily driving the vehicle along the roadway and its roadway sections (2a1), wherein said one or more electric stations ("s1") are activated solely during time periods or slots when the switch allotted to the station ("s1") senses, over a sensor, the presence of a vehicle belonging to the system, and "b" one or more vehicles propellable by means of an individual electric motor or motors, with the respective vehicle comprising a control circuit (100, "R1") controlling necessary power and adapted for creating necessary power control and/or speed control, said vehicle being provided with contact means on its underneath side, said contact means comprising current collectors which are displaceable up and down and sideways in relation to the conveyance direction of the vehicle, wherein said current collectors are adapted for mechanical and electrical contact with respective ones of the electric conductors (4a, 4b), wherein said elongated canalization extends along the roadway and the roadway sections, and wherein said vehicle comprises control equipment (100, 10) configured to control said contact means to provide said mechanical and electrical contact against said conductors (4a, 4b), wherein each road section is selected to a length exceeding the length of the vehicle, whereby each roadway section (2a1), that supports the vehicle, is, with its at least two electric conductors (4a, 4b), subject to a chosen voltage and current from the external electric power source ("III", 42), said two conductors being adapted to feed, over the contact means, its two adjacently oriented contacts related to said vehicle, the battery set and/or the motor of the vehicle, via a vehicle external switch allotted to said roadway section (2a1), characterized in a testing circuit configured to test an adjacently positioned and succeeding roadway section (2a2), with its at least two electric conductors (4a', 4b'), during time sequences when said succeeding roadway section is not subject to exposed voltage or current via a corresponding vehicle external switch, said testing circuit being configured to measure the impedance to ground potential using two resistors (R1, R2), one for each conductor (4a', 4b'), wherein a low voltage (U c) is applied via a conductor, wherein in an intact condition, the voltage over the respective resistors will be determined by the resistance of said resistors, and thereafter, if found in intact condition, said succeeding roadway section is to be provided with its DC or AC supply voltage from its external electric source ("III", 42), from its switch allotted to said succeeding roadway section (2a2) solely during a time sequence when said vehicle passes this roadway section (2a2) and that each roadway section, with its groove is formed for supporting at least two conductors and is adapted to be allotted the same two-phase supply voltage via its related switch, said testing circuit further being configured to test if the vehicle external switch is defective by being always closed, wherein the voltage applied via the conductor is measured and compared to the low voltage (U c), and if not corresponding, a protective engagement is enabled wherein a breaker disconnects the low voltage so that the entire succeeding roadway section (2a2) loses its voltage.