Monday, June 5, 2023

Arduino-based Automatic Liquid Dispenser

By Rakesh Jain

- Advertisement -

In this proposed automatic liquid dispenser whenever we want to fill the Water bottle/petrol in the vehicle, we just need to place the correct RFID card according to the need of quantity of petrol near the RFID reader. Then the ARDUINO reads the data from the RFID reader which in turn drives the ULN IC to further drive both of the relays for particular Water/petrol quantities and performs the action according to our/customer’s requirements.

This system helps in marriage or any function, we see that even after filling water from the water can, if children or anyone leaves the tab of the can open, then the water keeps flowing or the water gets wasted. Water saving will increase with this project it also provides security for the customers from various frauds occurs at petrol pump like Short Fueling of petrol by distraction, Tweaking petrol-dispensing machines using integrated chips.

Here in our proposed work the quantity of Water/fuel/petrol depends on the different delay time for each digital output pin of Arduino, which we provided during Arduino programming so as to drive the connected relay for the same instant of time which in turn activate the pump in water bucket or tank/fuel tank for the same time and as a result we will find particular quantity of Water/ fuel/petrol. Here in our proposed work we use Five different RFID tags for different delay times so as to drain 1/2 liter,1 liter, 1.5 liters, 2 liters, and 2.5 Liter Quantities. A solenoid valve has been used in this project so that the flow of water does not happen with much force.

Automatic Liquid Dispenser
Fig 1. Author prototype of Automatic Liquid Dispenser

List of Components Used in the Project

- Advertisement -

The materials required for the project are listed below.

Arduino Uno (MOD 1)1
RFID Tags/ Card 125 KHz4
ULN 2003 IC (IC1)1
Water Pump 220V AC (Pump1 )1
Solenoid Valve 24V DC1
12 V DC Power Adapter1
Relay 5V DC SPST ( R1, R2)2

Automatic Liquid Dispenser – Coding

First of all, in this project, we obtained the 12-digit unique identification number of the RFID tag on the serial monitor. To obtain the 12-digit id number upload the small code to the Arduino program shown in fig 2. and connect the EM 18 RFID module according to fig 3.

Code to obtain RFID card ID number
Fig 2. Code to obtain RFID card ID number
EM18 interfacing with Arduino Connection
Fig 3.. EM18 – Arduino Connection

Now Put the RFID Tag in front of the RFID Reader Module and See the 12-digit decoded value.

Here the decoded values for my RFID Tags are as follows (Refer table 2).

SR.NO. RFID TAG Image Decoded value from serial monitor(12-DIGIT)
1 0001948765 029,48221 0001948765 029 48221



2 0013946179 212,52547 0001948765 029 48221 5900D4CD4303
3 0013942651 212,49019 0001948765 029 48221 5900D4BF7B49
4 0001956746 029,56202 0001948765 029 48221 5A001DDB8A16
5 0001949492 029,48948 0001948765 029 48221 5A001DBF34CC

Next, prepare the code that checks the RFID card number and then gives a signal to the relay to dispense the water according to the RFID card here you need to change and set the card ID number according to your RFID card ID number.

Automatic Liquid Dispenser Code
Fig. 4

Automatic Liquid Dispenser – Circuit Connection

Next, connect all components according to the following circuit diagram.

Automatic Liquid Dispenser Circuit
Fig 5. Automatic Liquid Dispenser Circuit Diagram


Whenever a person will put the RFID tag in front of the RFID reader, both the relays will be ON, The first relay is to drive the water pump motor/Fuel pump motor and the second relay is to drive the solenoid valve. Here in this proposed project, we use ULN2003 relay driver IC to drive both relays.

We found that our circuit connection can fill half a liter of water/fuel in 16 seconds which means 1 liter in 32 seconds, 1.5 liters in 48 seconds, 2 liters in 64 seconds or 2.5 liters in 80 seconds. So whenever we want to fill half a liter of water/fuel we have to drive the relay continuously for 16 seconds and so on for different Quantities.

DIY Automatic Liquid Dispenser

RAKESH JAIN received a Master’s degree in VLSI, B.E. in electronics and communication, and DIPLOMA in electronics. He is currently working as an Assistant professor in ECE department at Geetanjali Institute of technical studies, Udaipur. His research area is SENSOR and Microcontrollers. He has 26 copyright and 3 Indian patents. He has also been honored with Mewar Scientist Award2023.




What's New @

Truly Innovative Tech

MOst Popular Videos

Electronics Components

Tech Contests