Water Level Indicator
This is the circuit diagram of a simple corrosion free water level indicator for home and industries. In fact, the level of any conductive non-corrosive liquids can be measured using this circuit. The circuit is based on 5 transistor switches. Each transistor is switched on to drive the corresponding LED when its base is supplied with current through the water through the electrode probes.
One electrode probe is (F) with 6V AC is placed at the bottom of the tank. Other probes are placed step by step above the bottom probe. When water is rising the base of each transistor gets electrical connection to 6VÂ AC through water and the corresponding probe. This, in turn, makes the transistors conduct to glow LED and indicate the level of water. The ends of probes of the water tank level indicator are connected to corresponding points in the circuit as shown in circuit diagram. Insulated Aluminum wires with end insulation removed will do for the probe. Arrange the probes in order on a PVC pipe according to the depth and immerse it in the tank. AC voltage is used to prevent electrolysis at the probes. So this setup will last really long. I guarantee at least a 2 years of maintenance-free operation. That’s what I got and is still going.
|Transistor (T1 to T5)||BC 548 or 2N2222|
|Resistors (R1 to R5)||2.2K 1/4 W|
|Resistors (R6 to R10)||22K 1/4 W|
|LED's (D1 to D5)||Color of your choice|
Use a transformer with 6V 500 mA output for power supply. Do not use a rectifier! We need pure AC. Use good quality insulated Aluminum wire for probes. If Aluminum wires are not available try Steel or Tin. Copper is the worst. Try the circuit first on a breadboard and if not working properly, make adjustments with the resistance values. This is often needed because the conductivity of water changes slightly from place to place. The calibration for simple water level indicator levels will vary according to the medium of liquid whose level is to be calculated.Â The type number of the transistors used here are not critical and any small signal NPN transistor will do the job. Few other suitable type numbers are BC546, BC107, PN2222, BC337, BF494, ZTX300, BEL187 etc. The circuit can be enclosed in a plastic box with holes for revealing the LEDs.
Water Level Indicator Circuit Diagram and Sensor Arrangement.
This is the most basic form of water level indicator used for measurement. If you need a fully automatic water level controller circuit then try this circuitÂ Water level controller. The circuit is fully based primarily on transistors. The sensing section is somewhat similar to this circuit but there is additional circuitry for switching the pump ON when the water level falls below a set level and the pump will be switched OFF when the tank is full. A few transistors, one 555IC and an electromagnetic relay are used for realizing the control section. The circuit is very simple cost-effective, reliable and many guys have successfully assembled it. I am also working on a float type water level indicator/controller using the float type fuel gauge mechanism used in motorcycles. The level sensor section is finished and now I am working on the control circuitry. I will add the circuit here as soon as it is finished
Note:- We have recently developed a much better and fully functional Water Level Controller circuit using 8051 Microcontroller.Â This water level controller monitors the level of the overhead tank and automatically switches on the water pump whenever the level goes below a preset limit. You may see the circuit and try it.
More Water level controller projects
Here is a large list of all our water level related projects;
- Water Level Indicator Using Arduino & Ultrasonic Sensor
- Ultrasonic water level controller using 8051Â
- Water level controller using arduino
- Water Level Controller using 8051
- Water level Controller
- Water level alarm circuit
- Liquid level indicator
We have more circuits and applications that you may like; Take a look below: