Rain Alarm Circuit

During this project, we’ve designed an easy Rain Alarm Circuit, which, upon police work rain, can activate a buzzer. Supported the buzzer, we are able to take necessary actions.

Rain Alarm Circuit

Rain Alarm Project could be a straightforward however terribly helpful project that detects Rain (Rain Water) associate degreed mechanically triggers an alarm or buzzer. Water could be a basic want in each one’s life. Saving water and correct usage of water is incredibly vital. Here is a simple project which can provide the alarm once there’s rain, so we are able to build some actions for rain water gathering and conjointly save the rain water for victimization it later. With the assistance of saving this rain water through rain water gathering, we are able to increase the amount of underground water by victimization underwater recharge technique. Rain water observer can detect the rain associate degreed build an alert; rain water detector is employed within the irrigation field, home automation, communication, vehicles etc. Here is that the straightforward and reliable circuit of rain water detector which may be made at low price.

Rain Alarm Circuit,Rain Alarm Circuit 555 ic,simple Rain Alarm CircuitBlock Diagram of Rain Alarm Circuit


The diagram of the Rain Alarm Project is shown within the following image. The 3 main elements of the project square measure the Rain Water detector, 555 Timer IC and Buzzer.

When the Rain Water detector detects the Rain, it sends an indication to the 555 Timer. The 555 Timer IC that is designed in its Astable Mode can then activate the Buzzer.

Block Diagram of Rain Alarm Circuit,Circuit Design of Rain Alarm Circuit

Components Needed:

  •  Rain detector
  • Buzzer
  • LED
  • Battery
  • Capacitor
  • Resistor
  • 555 Timers
  • NPN transistor

Circuit Design of Rain Alarm Circuit

The main component of this project is 555 Timer. It consists of 8 pins. On the right side of timer pin 6, 7, 3 are connected to resistors and buzzer. On the left side pin 2 are attached to capacitor and pin 4 are connected to NPN transistor and resistor. The remaining pin of timer 8 and 1 are connected to battery.

Working of Rain Alarm Circuit

We will see the operating of the straightforward Rain detector Alarm Circuit Project. Once rain falls on the detector, the metal Wires on the detector Board can begin conducting and shut the trail between the provision and base of the transistor Q2. As a result, the transistor Q2 can activate, which can conjointly activate the transistor Q1. This may activate the brilliant White semiconductor diode connected to the electrode of the transistor Q1. When the junction transistor Q2 is saturated, the condenser C1 is going to be shorted and can build the junction transistor Q3 to be turned ON. C1 can get charged by the resistance R4. When the junction transistor Q3 reaches the saturation mode, the Reset Pin of the 555 Timer, which is connected to the electrode of Q3, are going to be created positive. The 555 timer is designed in a stable Mode. Because the Reset pin of the 555 Timer IC is given positive voltage, it becomes active and that we can get a Pulse signal at the output pin three of the 555 Timer IC. This may activate the buzzer and also the alarm is activated. If you’re employing a speaker, electrical condenser C4, that is connected in between the Pin three of 555 timer and also the speaker, can block the DC signal and permits solely the variations within the signal that makes the speaker to form sound. The diode D1 won’t permit any reverse current from the timer. Because of the resistance R4 and electrical condenser C1, once the electrical condenser is totally charged, the junction transistor Q3 can get in to chop off mode once someday. As a result, the Reset pin of the 555 Timer IC won’t receive any positive voltage and also the speaker can stop creating sound. The time for 555 Timer to form speaker sound depends on the values of C1 and R4. When there’s no rain, the metal wire on the detector won’t conduct as they are doing not have any conductivity path. As a result, the detector cannot trigger the 555 Timer IC and there’ll be no alarm.

Applications of Rain Alarm Circuit

  1. within the irrigation, it’ll observe the rain and straightaway alert the farmer.
  2. in vehicles, once the rain detector detects the rain it’ll straightaway active the wipers and inform the motive force.
  3. in communications, it’ll boost the ability of the antenna and increase the signal strength to send or receive the signals.
  4. This could even be used if there’s a chemical rain conjointly. This is often quite common in industrial areas.



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