Inductive Water Level Indicator with Display using IC 74HC157 & CD4511

Introduction:

In this post, we are going to learn how to design Inductive Water Level Indicator with a Display. Most water level indicators are based upon the number of LEDs that glow to indicate the corresponding level of water in the container. But here we have designed Numeric Water Level Indicator using IC 74HC157 & CD4511. It is a digital version of the water level indicator using a 7-segment display to show the water level in numeric form from 0 to 9.

Check some advance projects here:
1. GSM Based Water Level Monitoring System with Arduino
2. IoT Based Water Level Control & Monitoring with ESP8266
3. Monitor Water Tank Level with GSM & ESP8266 on Blynk

Components Required:

Circuit Diagram: Inductive Water Level Indicator with Display using IC 74HC157 & CD4511

Circuit Explanation & Working:

The numeric water indicator circuit works off 5V regulated power supply. It is built around priority encoder IC 74HC147 & BCD-to-7-segment decoder IC CD4511 & common cathode 7-segment display.

When the water tank is empty, all the inputs of 74HC147 remain high. As a result, its output also remains high, making all the inputs of CD4511 low. Display at this stage shows ‘0,’ which means the tank is empty. Similarly, when the water level reaches L-1 position, the display shows ‘1,’ and when the water level reaches the L-8 position, the display shows ‘8.’ Finally, when the tank is full, all the inputs of 74HC147 become low and its output goes low to make all the inputs of CD4511 high. The display now shows ‘9,’ which means the tank is full.

Design Consideration:

It is recommended to use stainless steel wire without any corrosion for dipping into the water, else you may not get the desired result at the display.

The container should be wired like this as shown in the figure below.

The result is shown when dipped into the water from number 0 to 9: