Automatic water level controller


Walnut Innovations Automatic Water Level Controller


An automatic WLC (water level controller) is an essential equipment in a Home. Societies where there is a common water supply often install WLC's but individual home users tend to ignore this useful instrument.

There are several useful equipments that can make our lives easier, an Automatic WLC is one of them. You can not believe how much useful it is unless you have seen one. 

Walnut Innovations is coming up with a brand new Made In India model of their WLC which will soon be available on their website walnutinnovations.com and several other online shopping sites like amazon.in  

They have brought 3 models of their new WLCs Standard, VSP and 3Phase. 

Standard -  The standard model is for single phase monoblock or open well type pump sets. This is the one which is normally available on most of the homes

VSP - This model is for single phase vertical submersible pumpsets which need a starter

Three Phase - This model is for all 3 phase pumpsets

I will explain the Standard model which I have installed at my house. This WLC comes with 6 water level sensors. Normally we have an Underground tank where the water from the municipal water tap is collected, and then we pump the water to a Overhead water tank. 

These names Underground Tank (U) and Overhead Tank (O) are used to mark different connecting point of the sensors.



You can see OH, OL, C , C, UH, UL points in the controller in the picture above
Let us understand what it means. This will help you to install the WLC properly at your home
Upper Tank

OH - This is the uppermost sensor (Overhead High) placed in the overhead/ upper tank
OL - This is the middle sensor (Overhead Low) placed in the overhead/ upper tank
C - This is the bottom (Common) sensor  placed in the overhead/ upper tank

Bottom Tank


UH - This is the uppermost sensor (Underground High) placed in the underground/bottom tank
UL - This is the middle sensor (Underground Low) placed in the underground/bottom tank
C - This is the bottom (Common) sensor  placed in the underground/bottom tank

You need to measure the depth of your tanks to cut the wires of appropriate length. I will explain about how these sensors take part in the operation of the WLC

The motor will start if the water goes below OL and it will turn off after the water level reaches OH

So between the OL and OH is your one time water refill. You can decide how much water you want in pumped your tank in one go. The Bottom sensor C should reach all the way to the bottom of the tank.

In the Underground tank, the controller will check if the water is at the level of UH to start the motor. So you have to make sure that UH should be place such that it is below water level after the municipal water supply water is collected in your bottom tank. 

The UL sensor works as a dry run protection. It should be at least 2 inches above the foot valve

C is the bottom sensor and should be touching the bottom of the tank. 

Once you understand the functions of these different sensors, you will be able to decide the length of wire for each sensor. 

The wire suitable for connecting sensor is 2.5mm single core copper wire. you need to connect 3 sensors with three wires for each tank. 

water level sensor

Each sensor has two screws for fixing a wire. You can easily fix a wire to a sensor using a normal screw driver.

The length of each wire should be such that they can be fixed to some support outside the tank. This is to make sure that the wires and the sensors stay in place and do not slip deeper in the tank.

It is useful to mark the other end of each wire connected to the Sensors as OH,OL,C and UH,UL,C so that you can use these marking to decide which wire is which when connecting it to other cable.

We will need a longer cable to connect these sensor wires to the WLC. You need to measure the laying distance from the Upper tank and the location of the WLC. And the same from the bottom tank to the WLC. Suitable cable for these connections is 0.75mm 3 core cable

A 3 core cable has a black,red and green wires. You can decide a color combination to remember which wire is connected to which point.

I have chosen a combination like this

Red wire - OH and UH
Green wire - OL and UL
Black wire - C 

Lay the 3 core cable from the both tanks to the WLC location. 

The WLC has four holes in the back of the panel. You can use 1.5 inches screws to fix it after drilling holes in the wall. 

You should now connect the 3 core cable to the sensor wires, and after that connect the other end of the cable into the points OH, OL, C , C, UH, UL 

After connecting the sensor cables. You can connect the input and the output wires, You should make sure at this point that you have turned off the power supply to the input wires.

Once the input and the output connections are done, start the power supply, if the water level in the overhead tank is below the OL sensor and there is water above the UH level then you should hear your motor starting. You have successfully installed the Water level controller.

There is a button on the WLC. It is for manually turning the motor On or Off.

In case if you just want to place sensors in the Upper tank, then you need to short the points of the UH,UL,C. use two pieces of wires to connect UH to UL and UL to C. All other connections remain the same.

I hope this article will provide you sufficient information to  install an Water Level controller yourself.