摘要 |
A sump pump powered by a rechargeable battery has a circuit for monitoring the battery voltage and controlling charging of the battery. Four comparators monitor the battery and control two flip flops one of which operates the pump in cooperation with a float switch and the other of which turns the battery charging circuit on and off. The circuit is arranged so that when the battery is in its discharge cycle, the float switch controls the pump and the charging circuit comes on only when the battery voltage is in a low range. In the charging cycle, the pump is locked out in a low voltage range of the battery and is controlled by the float switch only in a high voltage range. |