Device for measuring liquid level and converting it to an electrical signal to send to other instrumentation.
A liquid level sensor is an instrument for measuring the height of a liquid and converting it to an electrical signal which is sent to other instrumentation to display, monitor, log or control the liquid level.
There are many different types of technology use to measure liquid level, there are sensors that can be mounted above the liquid such as ultrasonic or radar which bounce a sound or electromagnetic wave off the surface of the liquid and use the travel time to determine the distance from the liquid surface.
For liquid filled tanks there are sensors which can be attached externally, such as floats running up and down a liquid filled tube connected at the bottom of the tank, or a pressure sensor installed in a hole in the bottom of the tank which measures the pressure generated by gravity acting on the liquid.
Another method is to lower a probe into the tank and immerse it in the liquid such as a capacitive probe which detects the changing capacitance charge as the length of the probe is exposed to varying proportions of liquid and air, or pressure sensors which measure the pressure generated by gravity acting on the surrounding liquid.
Hydrostatic Level Sensors - Hydrostatic pressure sensing devices for measuring liquid level and converting it to an electrical signal to send to other instrumentation.
Water Level Transmitters with 4-20mA Output - 4 to 20 mA current loop output water level transmitters with a for use with process instrumentation for measuring the level of water in a water well, water reservoir, river or water storage tank.
Chemical Resistant Hydrostatic Liquid Level & Pressure Sensors - Pressure transmitters & transducers that are resistant to chemical corrosion for measuring the hydrostatic level of storage tanks or process pressures.
4-20mA Output Hydrostatic Level Transmitters & Sensors - Liquid level transmitters with a 4 to 20 milliamp current loop output signal for determining liquid depth or the fluid level by measuring the hydrostatic pressure.
Diesel Fuel Tank Level Sensors - Diesel fuel oil storage tank device for measuring diesel fuel level and converting it to an electrical signal to send to other instrumentation.
External Mounted Tank Level Sensors - External mounted level sensors for installing on the outside of a liquid storage tank to measure level of tank contents. 
Waste Water Level Sensors - Waste water Level sensors with open face flush diaphragms for measuring the hydrostatic pressure of sewage and effluent waste. Select a level sensor for mounting inside or external to a tank or sewer pipe.
Marine Approved Liquid Level Sensors - Devices with marine approval certification to use on ships for measuring liquid level and converting it to an electrical signal to send to other instrumentation.
Radar Liquid Level Sensors - Radar based sensing devices for measuring liquid level and converting it to an electrical signal to send to other instrumentation.
Ultrasonic Liquid Level Sensors - Ultrasonic echo sounding sensors for measuring liquid level and converting it to an electrical signal to send to other instrumentation.
Capacitive Liquid Level Sensor Probes - Capacitance sensing probe devices for measuring liquid level and converting it to an electrical signal to send to other instrumentation.
Submersible Diesel Tank Level Sensors - Diesel fuel oil storage tank device for measuring liquid level and converting it to an electrical signal to send to other instrumentation protected from diesel ingress when completely immersed in the fuel oil.
LMP307 Submersible Level Transmitter
LMP305 Borehole Level Transmitter
IMSTL IP68 Water Temperature and Depth Transmitter- IMCL Low Cost Submersible Pressure Sensor
- IWSL Potable Water Submersible Level Sensor
MTM3000 10mm diameter submersible miniature pressure transducer- 18.605 G Low Cost Submersible Diesel Fuel and Water Tank Level Sensor
DMP331P Hygienic Flush Pressure Transmitter- LMK331 Screw-In Ceramic Level Transmitter
- LMK458 Marine Approved Hydrostatic Level Transmitter
DMK 458 Seawater Low Range Pressure Transmitter- LMK351 High Overpressure Flush Level Transmitter
- 50m seawater depth & temperature sensor with SDI-12
- CIP protected dairy sensor for measuring level of milk in 6m high tank
- Underground rain water storage tank level sensor and readout for 2 metre depth
- 0.2 bar tank level pressure sensor for fuel oil up to 2m deep
- Low cost hydrostatic sensor for measuring depth of Diesel up to 2 metres
- Borewell water level sensor for 100m water height
- 200m deep well pump water level sensor, switch & display
- Arduino UNO compatible borehole water level sensor
- Utility manhole vault 4mH2Og range 0.5-4.5V out water level sensor
- Borehole drawdown low voltage power supply 25m depth sensor
- 40m RS485 Modbus RTU submersible borehole pump drawdown depth sensor
- Genset hydrostatic sensor for measuring level of small diesel tank up to 12 inches
Product Type Comparison Table
Please use the table below to compare the advantages and disadvantages of each liquid level sensor technology type versus application and specification parameters.
| Capacitive | Hydrostatic | Ultrasonic | Radar | |
|---|---|---|---|---|
| media contact | yes | yes | no | no |
| moving parts | no | yes | no | no |
| surface disturbance sensitive | no | no | yes | no |
| pressurised vessel | yes | more difficult | yes | yes |
| vacuum evacuated vessel | yes | more difficult | no | yes |
| installation position | top | side, bottom | top | top |
| thick fluids | no | yes with flush diaphragm | yes | yes |
| protrusion into tank | yes | no | no | no |
| sg density variation sensitive | yes | yes | no | no |
| fouling degrades performance | yes | yes | no | no |
| accuracy | low | high | high | high |
| cost | high | high | high | high |
Browse other help pages associated with the same topic group as this Liquid Level Sensor page.
- Hydrostatic Liquid Level Sensors
- Measuring liquid level in a sealed tank with a hydrostatic pressure sensor
- Measuring the volume of liquid in a horizontal cylinder tank
- Determining water tank volume using hydrostatic pressure
- Liquid Level Switches
- Float Fluid Level Detection
- Vibrating Tuning Fork Fluid Level Detection
- Conductive Fluid Level Detection
- Capacitive Fluid Level Measurement
- Hydrostatic Pressure
- Specific Gravity
- mH2O – Metres of Water Gauge at 4 deg C Pressure Unit
- mmH2O – Millimetres of Water Column at 4 deg C Pressure Unit
- Considerations for monitoring Landfill Water Level
- How do you measure the volume of a liquid using pressure
- Difference between vented and non-vented water level measurement
- Converting non-vented depth readings & barometric pressure to true depth
- Using Hydrostatic Pressure Transducers for Measuring Fluid Level
- Why are Submersible applications so demanding of Pressure Transducers?
- Determining the hydrostatic pressure range for a tank level sensor
- How to reduce submersible pressure sensor failures caused by moisture ingress
- Using a screw in or waterproof pressure transmitter to measure liquid level
- Using absolute pressure sensors to measure hydrostatic level
- Improve the electrical termination of vented submersible pressure sensors
- Determining the Signal Cable Length of a Suspended Liquid Level Transducer
- How does changes in Local Gravity affect Hydrostatic Pressure
- Are all IP68 Water Resistant Protection Ratings the same
- Liquid Level Measurement
- Problem with zero drift when installing submersible pressure sensor
- How to determine milk tank level and volume from pressure