GB1527606A - Automatic electric battery charging apparatus - Google Patents

Abstract

1527606 Battery charging systems CHLORIDE GROUP Ltd 20 Aug 1976 [20 Aug 1975 (2)] 34611/75 and 34612/75 Heading H2H Battery charging apparatus comprises means for providing a control signal which varies with the battery terminal voltage, a pulse generator controlled by the control signal so as to produce a train of pulses, the average repetition rate of which varies as the control signal and means for initiating the termination of the battery charging process when the rate of change of the average repetition rate falls below a predetermined value. The pulse generator may be of the type producing continuous trains of pulses or of the type producing groups of pulses. A battery is charged from an A.C. source by way of a contactor and a transformer rectifier device, the contactor being controlled according to the average repetition rate of the pulses. The apparatus includes an UP/DOWN counter and two further counters, one of which counts a period in the order of 30 minutes and the other a period of the order of 2 minutes. Whilst the battery is being charged, the pulses are applied during the counting period of two minutes separated by intervals of 30 minutes, the pulses being applied in the up mode and the down mode alternately. If at the end of a pair of counting periods the counter has not returned to the count it had before the first counting period, charging of the battery is terminated. The counting periods are so arranged that the second and subsequent counting periods have durations of about 4% less than the first counting period. Means are also provided such that if the battery terminal voltage is less than a predetermined value at the beginning of a charging period the charger is rendered inoperative. Furthermore if the output voltage of the charger rises above a second predetermined value the charger is switched off. Mains voltage compensation is provided together with lamps to indicate operation of the apparatus.