Protection circuit for battery chargers used with lead-acid batteries

摘要

The battery charger protection circuit has a series switch (13) to control the conduction of the charging circuit and has, between the output terminals (4,5) of the charger, a detector (8), which senses the battery voltage. In the absence of a fault at the charger output the detector delivers a current to actuate closing of the charging circuit. The detector has to inputs (9,10) connected respectively to the two outputs of the battery charger, and an output (11) connected to the control electrode of the series switch. The detector circuit uses a transistor in conjunction with a zener diode to check the voltage at the battery terminals.