On-board vehicular electrical power supply system

摘要

To permit elimination of separate exciter diodes of a vehicular three-phase alternator, and yet reliably ensure protection of the vehicular battery and provide an indication of discharge of the battery and hence possible failure of any excitation for the alternator, while additionally providing an indication of possible damage to the battery due to overvoltage conditions, the field of the alternator is separately excited from the battery through a voltage regulator connected to the main switch, and a low-voltage and high-voltage indicator is connected in parallel to the battery, preferably an LED triggered to illumination upon response of one of two threshold sensing circuits which sense undervoltage and overvoltage conditions of the battery beyond a predetermined voltage range.