Time switch circuit for household appliances - detects min. cell voltage to allow recharging and light LED

摘要

An electrolytic cell used for the supply of timers is household equipment can be recharged. The consumer equipment is coupled to the primary side of a transformer, with the secondary side connected to the bridge rectifier. The electrolytic cell normally discharges with a transistor in the blocked condition. An associated l.e.d. is not lit as long as the voltage lies above a min. threshold level. When the level has dropped below this value, the l.e.d. lights and a manually-activated contact may be closed to beging charging. A latch holds the charge circuit in operation.