This document describes a simple water level indicator circuit that uses a NE555 timer integrated circuit and activates a buzzer when water reaches a certain level. The circuit can be built on a printed circuit board along with a 9V battery and buzzer and mounted in a compact case. The sensor detects water and completes a circuit that causes the NE555 to produce oscillations activating the buzzer. The circuit provides a simple way to get an audible alarm for preset water levels and could be improved to indicate different levels. It has applications for fuel level indicators, water level controllers for buildings, and liquid level indicators in large containers.

2. WATER LEVEL
INDICATOR

3. ARSHAD ALI (10787)
Department of Electrical
Engineering
NUML Islamabad.

4. This simple water level indicator will activate
an active buzzer (e.g. BeStar BPT-23CX ) in
order to make a noise when a certain level of
water is being reached. Because the water
sensor and the command circuit are located on
the same printed circuit board, indicator,
together with its 9 V battery and the buzzer
can be mounted in a compact case. Obviously
the sensor, that is made by corossion, on the
board, must not be mounted directly on iron
or steel bathtubs but with a magnet atached on
the case.
INTRODUCTION

5. CIRCUIT DIAGRAM

7. List of COMPONENTS used
in the circuit

8. IC NE 555
• The 555 integrated circuit acts as a counter. When
activated by current entering in through pin 2, it starts to
count for a certain amount of time. When it has finished
counting it emits current from pin 3. This usually
activates other components such as LEDs or relays

9.  The combination of the resistor and capacitor determines
the length of the timing sequence. In general terms, if the
resistor and capacitor values are high the timing
sequence is long. If the values are low the timing
sequence is short

10. A buzzer or beeper is an audio signaling device, which may be mechanical,
electromechanical, or piezoelectric. Typical uses of buzzers and beepers
include alarm devices, timers and confirmation of user input such as a mouse
click or keystroke
The LED lights when current flows through it. In this circuit it indicates when
pin three is emitting current.
BUZZER AND LED

11.  Here is a simple water level alarm circuit using 555 timer that will
produce an audible alarm when the water level reaches a preset
level.The circuit can be powered of a 3V battery and is very handy to
use.
 The circuit is based on an astable multivibrator wired around IC1
(NE 555).The operating frequency of the astable multivibrator here
will depend on capacitor C1, resistances R1,R2 and the resistance
across the probes A&B.When there is no water up to the probes,they
will be open and so the multivibrator will not produce oscillations
and the buzzer will not beep.When there is water up to the level of
probes,some current will pass through the water,the circuit will be
closed to some extend,and the IC will start producing oscillations in a
frequency proportional to the value of C1,R1,R2 and the resistance of
water across the probes.The buzzer will beep to indicate the presence
of water up to the level of the sensing probes.
DISCRIPTION

12. THIS CIRCUIT CAN BE IMPROVED FOR
INDICATION OF DEFERENT LEVEL OF WATER

13.  1: Fuel level indicator in vehicles.

15. 3: AUTOMATIC WATER LEVEL CONTROLLER CAN BE USED
IN HOTELS, FACTORIES, HOMES APARTMENTS,
COMMERCIAL COMPLEXES, DRAINAGE, ETC., IT CAN BE
FIXED FOR SINGLE PHASE MOTOR, SINGLE PHASE
SUBMERSIBLES, THREE PHASE MOTORS. (FOR 3Æ AND
SINGLE PHASE SUBMERSIBLE STARTER IS NECESSARY) AND
OPEN WELL, BORE WELL AND SUMP. WE CAN CONTROL
TWO MOTOR AND TWO SUMPS AND TWO OVERHEAD TANKS
BY SINGLE UNIT.

16. 4:Liquid level indicator in the
huge containers in the
companies.