Alarm for Water Heater


It was a big problem in my house that, sometimes the Water heater left on for many hours after the use. It has a Thermostat to cut off but when the water cools, again it switches on. This caused a hike in electricity bill. Finally I found a solution. Just connected a Timer based alarm with the heater AC socket so that it will also switches on when the heater turns on. After 30 minute, it gives a loud alarm to remind that the heater is On. Alarm continues for another 30 minutes or till the heater is switched off.
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Simple Alarm Generator. Design Trick 8

You can make a simple alarm generator based on an oscillator to use in burglar alarm circuits. It uses only two transistors and a few other components. Oscillator is a circuit that generates AC pulses from DC. The AC pulses thus generated can be converted into audio frequency using a speaker. Let us see how it works.
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