please provide the project report for power supply resumption alarm circuit
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Here is an audio annunciator which can be useful in factories, industries, auditoriums, and theatres etc where generator is used when power fails. It produces an alarm for a predetermined time when power resumes.
power supply resumption alarm
The circuit is built around IC555 wired in monistable mode. The surge when power resumes triggers the monostable which switches transistor SL100 on. The relay energized and the bell or buzzer connected to N/O contacts of the relay operates. The preset time depends upon VR1 and C2. The Capacitor C3 connected to pin 2 of 555 should have low leakage.
PARTS LIST
Resistors (all ¼-watt, ± 5% Carbon)
R1, R2 = 10 KΩ
R3 = 470 Ω
VR1 = 1 MΩ (DELAY ADJ.)
Capacitors
C1 = 1000 µF/25V
C2 = 100 µF/25V
C3 = 1 µF/25V
C4 = 0.01 µF
Semiconductors
IC1 = NE555
T1 = SL100
D1 – D3 = 1N4001
Miscellaneous
X1 = 12V – 0 – 12V 500 mA secondary
F1 = Fuse
RL1 = 12V, 400Ω relay
230V buzzer