Water Tank Overflow Indicator Circuit diagram with Alarm using only one Mosfet

Hello friends ,
Welcome to Electronics Tube Blogspot. Today in this blog we will be sharing information about the very simple circuit for water tank full indication with an alarm tone. The most insane thing about the circuit is that it only uses a single n-channel mosfet along with few resistors.

The concept of the circuit is based on the fact that when gate and drains pin get shorted by the path provided by water, it turns the mosfet on due to which the circuit for the led and the buzzer gets completed and hence both led as well as the  buzzer gets turned on.
(*Mosfet has a very high input impedance hence it requires only few volts on its gate to turn on)

Below is the circuit diagram of the project for  Simplest water Tank Full Indicator with Alarm :
Simplest water Tank Full Indicator with Alarm
This is an amazing project for electronics learners. Want to try building this project ?
Watch our Video Tutorial on Simplest Water Tank Full Indicator with Alarm

Components List :
R1 = 1M
R2 = 2.2K
Mosfet : N-Channel  IRF540N or IRFZ44N
Buzzer 1
Battery : +5 to 12 volts
Datasheet for IRF540N