Liquid Level Sensor

About: Loves Electronics, Bicycle Traveling, Teaching, also loves Nature & People. Creates more scrap from the scrap.

I wanted to make a Water level control sensor
but of non contact non Electronic & cheap one !

Took Plastic hand pump, Removed Rubber 'O' ring from the Piston
So now the piston moves freely without any friction
Cut liquid container and fixed with Epoxy in to Piston drilling a hole.
Ceramic magnet ( very light) sticked on the piston's top flange.
Reed switch fixed at the Top cover Nozzle side.
Now the Hand pump fixed up right So that Liquid container floats on
water and pushes the piston upwards as the level starts increasing.
When the piston goes fully upwards the magnet actuates the Reed switch
which ultimately cuts Off Motor Pump.

This costs me only Rs 40.
and it works smoothly !
No Electronics, No maintenance, No physical contact
No corrosion, No Cleaning of Electrode it's Amazing !
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    7 Discussions


    6 years ago on Introduction

    nice, but eventually you'll run into problems as your reed switch will get magnetized and stick. Oh well, replace the reed switch then

    2 replies

    Reply 6 years ago on Introduction

    Last 5 years I am using this sensor and does not have any problem, If you keep the load current through reed switch contact as minimum as possible (at 5 volt).
    And if at all fails ...simple replace it