• External installing,no-touching to liquid inside
  • Not effected by color, light,etc
  • Electronic technology,no moving parts,longer working life
  • Low cost for non-metal containers/pipes/tubes
  • Voltage output,high/low electric level,NPN /PNP output way for different control wire.
  • Suitable for water, alcohol, acid, alkaline, etc and powdery particle

Non contact water level sensor is designed to provide external liquid level measurement for non-metal containers and  non-metal pipe/tube.The typical application is water tank level sensor,etc. With our patented technology, the non contact liquid level sensor can detect container level by simply attaching the sensor onto external surface of containers. That means it won't contact liquid and don't need to open closed container or cut it. Thus, it doesn't pollute the liquid. The non-metal material can be plastic, glass,ceramics,etc,and typical non-metal containers mainly have tank,pipe,bottle,barrel,drum,etc.

The non contact liquid level sensor is developed on advanced signal process technology by high speed signal process chip. It can measure liquid level of closed container by penetrating the wall of container. The liquid level sensor is usually fixed on the vertical side of non-metal container, and doesn't need to cut holes. It is easy to install and don't stop manufacturing. It can still work well even though the containers have various of poisonous materials,strong acid, strong alkali,etc.

With low cost and good performance, the non contact water level sensor switch has been widely used in water tower, pipe, water tank, environment protection device, medical device, close-stool, whirlpool tub, coffee machine maker, water dispenser, etc.

Typical Application:

  • Home Appliances
  • Toilets
  • Beauty SPA equipment
  • Bathroom Intelligent Control
  • For drinking water and water purification
  • Medical and food equipment
  • Chemistry equipment
  • Aquaculture
  • Solid level monitor


  • Induction container wall thickness: 1-10mm(Typical), max 100mm thickness optional(Part of model)
  • Power supply: 5-24VDC
  • Environment temp.:0 - 85 Deg.C
  • Output way: NPN,PNP,High/Low electric level,Voltage outoput, RS485 optional
  • Output voltage(high electric level):InVCC
  • Output voltage(LOW electric level):0V
  • Protection class: IP65 or IP67 optional
  • Induction surface material: ABS,PBT
  • Relative humidity:5%-95%

Ultra Mini Non Contact Water Level Sensor

Very Low Cost and Very Small Size

Miniature non contact water level sensor is designed for project with ultra small size and low price. Its structure is compact and flat that is different from the white version above. The flat structure makes it easy to fix tightly. It is more suitable for water and similar liquid. It is used for non-metal containers,e.g. plastic, glass,etc. Its cable and connector can be made as requirement. The non contact water level sensor has been widely used for many projects.

The non contact water level sensor provides single point level measurement and monitoring with high/low electric level output. When detect the level from external container wall, it directly produces 0V low electric voltage, when no level is found,it produces 5V high electric level. One piece of level sensor is used to monitor one single point level. If you want to high and low level, please use two pieces: one is for low level,the other is for high level. The non contact water level sensor doesn't need special MCU to produce electric level signal,and the level sensor itself can send it too. This can reduce your time and cost.

Technical Specification

  • Level accuracy:+/- 1.5mm;
  • Power supply voltage:4V-5VDC
  • Max container wall thickness:2.5-3.5mm(Plastic container,if other material, the value may vary)
  • Current consumption: 100mA
  • Power consumption: 200mA
  • Working temperature: -20-+70 Deg.C.
  • Output way: High/Low electric level
  • Output voltage(high electric level):True value:0. Output voltage:<0.3mA. Output current:<10mA
  • Output voltage(LOW electric level):True value:1. Output voltage:<Vcc. Output current:<20mA
  • Induction surface material: ABS
  • Relative humidity:5%-95%
  • Protection class: IP65

     Non Contact External Switch for Water Tank Level Sensor

Non contact water level sensor can be used as water tank level sensor and provide external monitoring for liquid tank level. Here water tanks don’t just refer to standard tanks, but also include other shapes and different volume, e.g. shapes can be round tank, square tank, rectangle, or other irregular shapes, and volume can be from minor to huge.

Even though liquid tanks are closed with pressure and high temperature (over 100 Deg.C.), part of our non contact water tank level sensors can work normally. Under such application, ultrasonic level sensors and hydrostatic level transmitter may not work well for most of application.

For water tanks, the tank material may be different, e.g. plastic, glass, ceramic, steel, even wood, etc. In order to make a simple difference, we can totally divide them into 2 categories:
1). Non-metal Tanks
2). Metal Tanks
Note: Please check 2 pictures above for reference.

                                                   Non Contact Water Level Sensor for Non-metal Tanks
For this, things have been very simple. We have versatile models to meet different non-metal tanks with different material, different thickness value, different shapes, different fluids, different temperature, etc. Customers just tell us their detailed requirement, and our engineers will recommend a proper model after comprehensive consideration.

                                               External Water Tank Level Sensor for Metal Tanks
For metal tanks, we have non contact tank level sensors developed on the basis of ultrasonic technology. Such ultrasonic tank level sensors supports bottom installing or side mounting from external. But their price is higher than the low cost non-contact model. Thus, many customers prefer to this model limited by project budget, especially the project is common water tank level. For this requirement, there are 2 solutions as below:

Solution 1: Cut a hole or 2 holes at the side of a metal tank. Then block the holes with plastic plugging then attached non contact level sensor onto the external surface of plugging.
1 hole is used to measure a level point, and 2 holes are used for high/low level monitoring.

Solution 2: Cut 2 holes at the side of a metal tank, then install a plastic tube at vertical direction. After that, user can attach non contact level sensors to the vertical plastic tube.

If you have any question about the solutions, please feel free to contact us.

Except non contact water level sensor, we have higher performance non contact level sensor for other liquids, including oils, blood, honey, acid, etc. If you have such requirement, please visit Non Contact Liquid Level Sensor to learn more details.

If you want to measure liquid level in metal container, please visit  clamp on ultrasonic level controller.

Pipe material is non-metal,e.g.plastic,PVC,glass,rubber,acrylic,ceramics(no water absorbent),etc. The non-contact level flow switch is low cost solution.


  • Level accuracy:+/- 1.5mm;
  • Power supply: 5-24VDC
  • Current consumption: 5mA
  • Response time:50S
  • Environment temp.:0 - 85 Deg.C
  • Max output current: 1-100mA
  • Output way: NPN,PNP,High/Low electric level optional
  • Output voltage(high electric level):InVCC
  • Output voltage(LOW electric level):0V
  • Protection class: IP67
  • Induction surface material: ABS
  • Relative humidity:5%-95%
  • Dimension:28x16.9mm(check the picture below)

Application condition for pipe(liquid):

  • Dynamic viscosity<10mPaS, normal measurement.
  • 10mPaS<Dynamic viscosity<30mPaS, test may be effected.
  • Dynamic viscosity>30mPaS, can't measure.

Note: As the temperature becomes higher, the viscosity is down.Most of high viscosity liquid are easily effected. Please pay attention to temperature changing while measuring viscosity liquid.

Sensitive (Pipe size&Pipe wall thickness)


Get More Tank Level Sensor

For more tanks, there are more different types of tank level sensors. The following are often used advanced tank level sensors:

  • Ultrasonic Level Sensor/Transmitter
  • Radar Level Transmitter
  • capacitive tank level sensor
  • Magnetostrictive liquid level meter