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Wireless Battery Operated Water Tank Overflow Alarm or Transmitter Answered

In India and worldwide water, availability is a huge issue so saving water is most important work these days for the environment. As like most of the Indian families using water tank to store water and use them later. The main issue is that wastage of water once water tank got filled and most of the water tank fixed on the rooftop. There are lots of devices available in the market to warn overflow tank but most of comes with bulky wires and connection to show the water level or water overflow warning.

But I want to make a simple battery operate design/circuit for a water tank that transmits water overflow signal every 8 or 10 seconds to the receiver. For the signal receiver, there is no issue of power but for transmitter power, an important factor and this is must that transmitter circuit works on battery for a long time.

So Here I want to design a circuit works on battery (3v to 5v). A circuit with two wire fix at the top of the water tank or on the sidewall and circuit check wires connection for water touch them every 8 to 10 sec. If water touched the wire transmitter release a signal (go to sleep mode again for next 10 sec) to the receiver and receiver worn by a small buzzer for 10 sec. Again after 10 sec transmitter check the water level and release a signal to the receiver. Similar water tank alarms comes costly around 90$ to 150$. I want to use AtTiny85 or min Arduino, Wireless module 433mhz to save money. So please help me start this project by programming or another way to finalize this project and help me save water.


I wouldn't do something with a circuit with bare contacts to be honest, but woth a float switch. For example this one: https://www.aliexpress.com/item/110V-PFS8510-Level...

And for sure not one that is with bare contacts, or inductive. They corode pretty fast and are meant to not be submerged for lengths of time.

While this switch is rated for 110V they are rather dumb and also are really just a switch.

Add a cheap 433mhz transmitter for the sensor thing and a cheap receiver for the buzzer thing: https://www.aliexpress.com/item/RF-wireless-receiv...

Add preferably a mcu at both ends, for examle an arduino nano add two cells per mcu. Connect it bypassing the onboard voltage regulator. (it has most commonly pins for that).

Connect the power of the transmitter to an io pin as well to conserve power, probably via a transistor or mosfet because the power draw is too high for just the io pin probably.

and forgot to add, make sure you use the sleep feature of the mcu as well. This greatly helps preserving battery as well

Also you can wake up the mcu either by an interupt from a input (aka the switch). or a timed cycle. both can be combined as well. and doesn't have to be active always either.

(gah, I wish there was an edit function)

Thank you for your suggestion but I am looking battery oriented solution using ready to use 433mhz Tx should transmit a signal every 8 sec or above if water touched the wires.