TIME SWITCH FOR NIGHT POWER SUPPLY

PURPOSE:To prevent waste use of power, by supplementing a power failure time to make an energization time for a load equal to a set energization time while a continuous energization time is kept from exceeding the energization time. CONSTITUTION:When occurring during an energization time zone, a power failure is detected 21 and a power failure detection signal is inputted into a computing means 22, which works to count 25 a power failure time. Then, the means 22 discriminates the restoration of power by the stoppage of the power failure detection signal to end the counting of the power failure time and the power failure time counted 25 is stored 36. Then, the power failure time stored 36 is read out to be set on an internal register of the means 22. Moreover, when the energization time ends, time with an energization supplement time added thereto is compared with the current time to discriminate the end of a power failure supplement time and the ON state of an output relay 38 is continued. When the end of the power failure supplement time is discriminated, the relay 38 is turned off. When the subsequent energization start time is reached before the end of the power failure supplement time, the cancellation of the next energization is judged 40 and the results of the judgement are maintained during the subsequent energization time zone.