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Liquid Detectors / Liquid Sensors:   #'s - D       E - S       T - Z

 

Last Updated: November 22, 2021 02:41 PM

Circuits Designed by Dave Johnson, P.E. :

Water Cistern Level Alarm  -  I received an unusual request from a Discover Circuits visitor a while back.  The guy had a deep water cistern which has to be filled when nearly empty. The cistern was described as a deep cylindrical tube, holding 1000s of gallons of drinking water.  Periodically, the cistern is filled from a tanker truck, when the water inside reached a critical level.  The guy wanted a simple circuit he could build which would flash an LED when the water level reached a certain depth.  That flasher would tell him it was time to order more water. . . Circuit by David A. Johnson P.E.,  04/27/14


Water Filling Station Controller  -  This circuit was requested by a company needing a simple way to fill a large tank with water with little fuss.  They wanted a low tech method to automatically fill the tank with water without constant monitoring.  They wanted to press a single pushbutton switch and then walk away . . . Hobby Circuit designed by Dave Johnson P.E.,  04/24/11

Water Flowing in Pipe Indicator  -  The vibrations associated with water flowing through a pipe are picked up by an inexpensive piezoelectric wafer.  The signal from the wafer is first boosted by a micropower transistor Amplifier and then fed to an ultra low power voltage comparator.   When the vibration signal has sufficient amplitude, a FET transistor switch is activated…Circuit designed by Dave Johnson P.E., 6/06/2009. . . Circuit by David Johnson P.E.,  07/26/09


Water Level Monitor  -  This system operates much like a classic float switch but without any moving parts.  The illustration shows how a system using two copper coils sealed inside a plastic pipe, can detect the level of water outside the pipe.  Whenever the water level is lower . . . Hobby Circuit designed by David Johnson P.E.,  07/09/06


Water Seepage Alarm  -  This simple circuit sounds a beeper when its electrodes detect water. It is powered by a single 1.5v N cell. A small 1.5v button battery will also work . . . Hobby Circuit designed by David Johnson P.E.,  06/11/00


Water Seepage Monitor  -  A while back I received a request from a company who needed a water seepage detector.  They wanted a device that ran on 24vac and detected water using a fully isolated circuit.  They wanted a circuit which switched off 24vac to a load when water was detected. . . Circuit by David A. Johnson P.E.,  01/16/11

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Links to electronic circuits, electronic schematics and designs for engineers, hobbyists, students & inventors:

Tank Water Level Indicator -  A little over five years ago, before water became a "cause celebre", we published a design for a simple tank water level indicator.  Now, with thousands of home water tanks being installed every year (and prompted by many requests for such a project) , we thought it time to resurrect the idea, albeit with a couple of tweaks.__ SiliconChip

Ultrasonic Water Tank Level Gauge -  Do you have a tank to collect rainwater? Do you know how much water is in it? This ultrasonic tank level gauge fires an energy burst which bounces off the surface of the water ? and then a microcontroller calculates how far down the tank water level is.  Clever, eh! __ SiliconChip

Versatile Water Level Controller -  This simple, economical and versatile circuit switches on the motor pump when water in the overhead tank falls below the lowest level and turns it ‘off’ when the tank is full....__ Electronics Projects for You

Water & vandal-proof keypad uses piezoelectric disc as sensor & buzzer -  04/21/14  EDN Design Ideas:  An ingenious and low-cost method to create a rugged “Ui”.  This design was done to get a sealed keypad for very wet environments (in my particular case, showers for swimming pools).  The keypad needed to be able to detect slight pressure on a stainless steel plate 0.4mm thick.  Apart from water protection, the solution offers an esthetical finish, as the user side is absolutely flat, with nothing visible other than the silkscreened print.  Another advantage of this type of keypad is that it is vandal-proof Design by Francesc Casanellas

Water Activated Alarm -  The circuit uses a 555 timer wired as an astable oscillator and powered by the emitter current of the BC109C.  Under dry conditions, the transistor will have no bias current and be fully off.  As the probes get wet, a small current flows between base and emitter and the transistor switches on.  A larger current flows in the collector circuit enabling the 555 osillator to sound __ Designed by Tom 

Water Activated Relay -  in his circuit Marin has used two transistors wired as a high gain compound pair.  Transistor T1 may be a 2N2222A and T2 a BC108.  The current gain will be the product of each transistors beta, which will be a minimum of 140 x 110 or 15400.  The power supply used can be any voltage from 4.5 to 15 volts,  __ Designed by Marin Lukas

Water Alarm -  The LM1830 fluid detector IC from National Semiconductor is designed to be able to detect the presence of fluids using a probe.  This chip requires a relatively high supply voltage and is not the most frugal power consumer.  it is also quite specialised so unless you are buying in bulk the one-off price is not cheap must register on this site __ Designed by Elecktor July/Aug, 2010

Water Cistern Level Alarm -  I received an unusual request from a Discover Circuits visitor a while back.    The guy had a deep water cistern which has to be filled when nearly empty.  The cistern was described as a deep cylindrical tube, holding 1000s of gallons of drinking water.    Periodically, the cistern is filled from a tanker truck, when the water inside reached a critical level.    The guy wanted a simple circuit he could build which would flash an LED when the water level reached a certain depth.    That flasher would tell him it was time to order more water. . . Circuit by David A. Johnson P.E.-April, 2014

Water Drain Pump Controller -  A hole needs to be dug at the lowest place in the cellar that have water incoming problems.  The hole is about 0.5 x 0.5 x 0.5 meter, at the bottom a large water pump is mounted.  Then the different water levels was measured, so we know how to make the sensors.   __ Designed by Thomas Scherrer OZ2CPU

Water Filling Station Controller -  This circuit was requested by a company needing a simple way to fill a large tank with water with little fuss.    They wanted a low tech method to automatically fill the tank with water without constant monitoring.    They wanted to press a single pushbutton switch and then walk away.    in their application, the water tank is first filled to a certain level.    The fixed volume of water is then slowly drained off into a second tank, where the water is mixed with another material.    The empty tank is then ready to be filled again, for another cycle. . . . Hobby Circuit designed by Dave Johnson P.E.-April, 2011

Water Flowing in Pipe Indicator -  The vibrations associated with water flowing through a pipe are picked up by an inexpensive piezoelectric wafer.    The signal from the wafer is first boosted by a micropower transistor amplifier and then fed to an ultra low power voltage comparator.     When the vibration signal has sufficient amplitude, a FET transistor switch is activated…[Circuit designed by Dave Johnson P.  E.  , 6/06/2009]. . . Circuit by David Johnson P.E.-July, 2009

Water Level Alarm -  A circuit that offers visual indication of fluid level in a vessel, with a switchable audible alarm.  Example uses would be to monitor the level of water in a bath or cold storage tank.   __ Designed by Andy Collison

Water Level Alert -  This circuit will emit an intermittent beep (or will flash a LED) when the water contained into a recipient has reached the desired level.  it should be mounted on top of the recipient (e.g.  a plastic tank) by means of two crocodile clips, acting also as probes.__ Red Free Circuits

Water Level Control/Monitor -  A simple way to control the level of any liquid in any container.   __ Designed by Jose Pino

Water Level Controller -  Supply your own water pump for this water level controller. __ Contact Jameco Electronics

Water- Level Controller -  in most houses, water is first stored in an underground tank (UGT) and from there it is pumped up to the overhead tank (OHT) located on the roof.  People generally switch...__ Electronics Projects for You

Water Level Controller-Cum-Motor Protector -  Many a time we forget to switch off the motor pushing water into the overhead tank (OHT) in our households.  As a result, water keeps overflowing until we notice the overflow...__ Electronics Projects for You

Water Level Detector -  Schematic + info + pictures __ Designed by Lennie Zink

Water Level Indicator -  This water-level indicator uses a 7-segment display, instead of LEDs, to indicate the water level (low, half and full) in the tank.  Moreover, a buzzer is used to alert you of water overflowing from the tank.  The circuit shows the water level by displaying L, H and F for low, half and full, respectively.  The circuit uses five sensors to sense the different water levels in the tank.__ Learning Electronics

Water Level Indicator with Alarm -  Here is a simple, versatile circuit which indicates the level of water in a tank.  This circuit produces alarm when water level is below the lowest level L1 and also when...__ Electronics Projects for You

Water Level Indicator with alarm -  This circuit not only indicates the amount of water present in the overhead tank but also gives an alarm when the tank is full.    The circuit uses the widely available CD4066, bilateral switch CMOS IC to indicate the water level through LEDs.  When the water is empty the wires in the tank are open circuited and the 180K resistors pulls the switch __ Designed by Radioland.nt.au

Water Level Monitor -  This system operates much like a classic float switch but without any moving parts.  The illustration shows how a system using two copper coils sealed inside a plastic pipe, can detect the level of water outside the pipe.  Whenever the water level is lower . . . Hobby Circuit designed by David Johnson P.E.-July, 2006

Water Pump Controller -  Here is a simple circuit for controlling water level in an overhead tank.  The main components of this pump controller are a step-down transformer, a 24V AC double-changeover relay, two floats...__ Electronics Projects for You

Water Pump Controller 2 -  A water pump controller senses the level of water in a tank and drives the water pump. The circuit described here is built around timer IC 1 (555). When the water level...__ Electronics Projects for You

Water Pump Hysteresis -  A simple circuit to prevent a pump being damaged by being turned on and off rapidly (multiswitching).   __ Designed by REUK-Renewable Energy UK website

Water Pump Relay Control -  Water reservoir automatic level control; Simple circuitry - 12V supply __ Contact Flavio Dellepiane, fladello @ tin.it

Water Seepage Alarm -  This simple circuit sounds a beeper when its electrodes detect water.  it is powered by a single 1.5v N cell.  A small 1.5v button battery will also work . . . Hobby Circuit designed by David Johnson P.E.-June, 2000

Water Seepage Monitor -  A while back I received a request from a company who needed a water seepage detector.  They wanted a device that ran on 24vac and detected water using a fully isolated circuit.  They wanted a circuit which switched off 24vac to a load when water was detected. . . Circuit by David A. Johnson P.E.-January, 2011

Water Sensor Alarm -  This small water sensor alarm circuit makes a loud warning sound when a humidity sensor detects a quantity of water.  This circuit assembly is an application of low power comparator LM1801 made by National Semiconductor.  The reference voltage for the integrated circuit is fixed with the help of R2.  When pin 4 of the LM1801 __ Designed by Popescu Marian

Water Tank Controller -  Frequency Counter project detailed here is based on PIC 18F4550 for which design and firmware/software support is given by Fox Delta Team.  There are many PIC  based frequency counters out there but this one will stand apart from others. __ Designed by Nina Gajjar

Water Tank Level Meter, Pt.3: the Base Station -  Designed to team with up to 10 Water Tank Level Meters, this Base Station lets you monitor water levels from a remote location (eg, inside your home).  As a bonus, it also includes an option for electric pump control.__ SiliconChip

Water-Leak Detector Uses 9V Batteries -  05/27/10 EDN-Design Ideas   The design uses Maxim integrated Circuits '  MAX934, an ultra-low-power quad comparator with a built-in 1.2V reference.  The chip uses about 6 μA.  IC 1A , R 1 , and R 2 provide water-leakage detection.  R 1 is the water probe, which can be two bare copper wires wrapped in a sponge.  R 1 has high impedance when the sponge is dry, so IC 1A 's output stays high Design by Yongping Xia, Navcom Technology, Torrance, CA

Water-level Alert -  This circuit will emit an intermittent beep (or will flash a LED) when the water contained into a recipient has reached the desired level.  it should be mounted on top of the recipient (e.g.  a plastic tank) by means of two crocodile clips, acting also as probes.  if a deeper sensing level is needed, the clips can be extended by means of two pieces of stiff wire (see pictures). __ Contact Flavio Dellepiane, fladello @ tin.it

Water-Level Controller -  Here is a simple, automatic water level controller for overhead tanks that switches on/off the pump motor when water in the tank goes below/above the minimum/maximum level.  The water level is...__ Electronics Projects for You

Water-Level Indicator -  Many a time we forget to switch off the motor pushing water into the overhead tank (OHT) in our households.  As a result, water keeps overflowing until we notice the overflow...__ Electronics Projects for You

Water-Level Indicator -  Many a time we forget to switch off the motor pushing water into the overhead tank (OHT) in our households.  As a result, water keeps overflowing until we notice the overflow...__ Electronics Projects for You

Water-level Indicator -  Simple, two-wire, remote monitoring unit; Three-LED level display, 9V battery powered __ Contact Flavio Dellepiane, fladello @ tin.it

Water-level Indicator -  Simple, two-wire, remote monitoring unit; Three-LED level display, 9V battery powered __ Contact Flavio Dellepiane, fladello @ tin.it

Water-Level Indicator using 7-Segment Display -  This water-level indicator uses a 7-segment display, instead of LEDs, to indicate the water level (low, half and full) in the tank.  Moreover, a buzzer is used to alert you of...__ Electronics Projects for You

Water-level Sensing & Control -  This is a simple but reliable circuit for your sump-pump, aquarium, boat, or whatever, but water only.  Please be careful when working with 115Volt line voltage!  Take every precaution to avoid electrical shock.  Unplug the power before making changes or touching resistor R1.  Murphy's Law applies to all of us!   __ Designed by Tony van Roon  VA3AVR

Waterpump Safety Guard for Fish-pond -  The circuit below was developed to guard the fish pond.  in this case to prevent that the pump sucks just air when the water level get below the pump.  When the water filters get saturated and dirty, the water level behind the filter gets to an unacceptable level.  You can see this when the pump also produces air bubbles in the water __ Designed by Tony van Roon  VA3AVR

Water-Tank Overflow Indicator -  Water is a vital but scarce natural resource.  To prevent water wastage, this water-tank overflow indicator comes in handy.  it gives audio as well visual alarm whenever the water tank overflows. __ Electronics Projects for You

Web-Based Water-Level Monitor & Pump Controller -  Several articles about water-level controllers for overhead tanks have been published in earlier issues of EFY magazine.  But the project we are going to share today is new and unique.  So...__ Electronics Projects for You

Well Pump Controller -  Having a reliable system to pump out a sump pit is essential as mistakes and failures can lead to serious flooding and enormous expense.  in our article Sump Pump Control System we introduced a selection of electronic solutions to the following problems __ Designed by REUK-Renewable Energy UK website

Wireless Liquid Level Sensing for Restaurant Applications -  Since restaurants often make much of their profits on drinks, it is critical for servers to offer refills in a timely fashion.  We propose wireless liquid level sensing glassware to aid in this task. Specially instrumented glassware detects fluid levels via a high-resolution capacitance measurement. A coil embedded in the table inductively couples power to the glasses, and provides a path for data exchange.  Our prototype glass uses a standard microprocessor and a small number of passive components, making it extremely inexpensive. __ Designed by Paul H. Dietz; Darren Leigh; William S. Yerazunis

Got Designs?
Please eMail
if you want me to link to and/or post your original design Thanks.


Liquid Detectors / Liquid Sensors:   #'s - D       E - S       T - Z


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