Application of Water Level Measurement with it’s PLC Logic

Water Level Measurement with Auto Start/Stop

In this article, we are going to see a simple water level measurement application with an auto start/stop of the motor. We are implementing this simple logic with the use of low and high sensor which is installed in the water tank.

Here, you can find an overview of this application.

water level measurement

As shown in the below image, we have two sensors, Sensor1 will detect whether the water is present in the tank and the Sensor2 will detect the tank is full of water.

There may be three cases in this scenario.

Tank Level Measurement

1. Case-1

In the first case, there is no water present in the tank. So both the sensor-1 and sensor-2 are in their ideal status.

2. Case-2

In the second case, there is some amount of water in the tank or we can say that the water tank is half filled up. So in this case sensor-1 detects that there is water inside the tank, but sensor-2 is in its ideal status. There is no water at sensor-2. It means that the tank is not filled fully with water.

3. Case-3

The third case represents that the tank is filled fully with water. There is water at both sensor-1 and sensor-2.

In both the first and second cases, we have to give the motor to remains ON because the tank is only partially filled with water. But in the third case, we have to stop the motor because in this case tank is filled fully with water.

PLC Ladder Logic Conversion

To implement this logic in PLC programming, let’s consider sensor1 as I0.0 and sensor2 as I0.1 inputs and the motor will be as Q0.0 output.

Let’s implement this logic in the ladder language.

water level measurement

Let’s see this logic in the animated image.

tank level measurement

I hope you like this article. This is a very simple example of tank water level measurement and its implementation in ladder logic. Comment your feedback about the article in the comment section below.


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