Electric power supply

The arrangement has auxiliary batteries (15) or accumulators associated with individual or grouped loads (17-21) which can be connected via a charging circuit and a changeover circuit to a main battery, esp. the vehicle battery (11) or generator. In normal operation the load or groups of loads is/are connected to the auxiliary battery. If the auxiliary battery fails or discharges a changeover (14) is made so that the loads or a group of loads is or are supplied from the main battery.