After soldering the components as per circuit diagram connect the power supply and turn it on.
Power supply failure detector.
The only power failure device with plug detection.
A reference voltage storage unit 29 which in the off state of a power supply switch.
If your plug becomes unplugged from the power fail alarm itself this is detected electrically and the alarm sounds.
It employs an electrolytic capacitor to store adequate charge to feed power to the alarm circuit which sounds an alarm for a reasonable duration when the mains supply fails.
But the alarm circuit presented here needs no additional supply source.
Most of the power supply failure alarm circuits need a separate power supply for themselves.
It is very helpful to indicate the loss of power supply to some power critical instruments such as a lifecare device installed in a hospital.
A selectable snooze alarm feature will cause the alarm to come back every 30 minutes until power is restored.
Working of power supply failure alarm.
Will alarm for 72 hours straight with the supplied lithium battery.
The present invention is characterized by being provided with.
The front end of the design is a simple ac230v mains presence sensor built around one popular photocoupler pc817b oc1.
The circuit also includes a standard on rechargeable 6f22 9 v battery bat in power supply and a low voltage slide switch s1 as the master power on off switch.