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.
- ATEX Approved Liquid Level Sensors for Hazardous Areas - European hazardous area ATEX approved sensors for liquid level measurement in intrinsically safe installations on petrochemical, pharmaceutical, landfill and sewage treatment sites.
- 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.
- 0-10 Volts Output Hydrostatic Sensors, Probes & Transducers - Analog output hydrostatic sensors with a 0 to 10 volt amplified output signal for measuring liquid head pressure or fluid level.
- 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.
- Sea, Brackish or Salt Water Submersible IP68 Depth & Level Sensors - IP68 rated transmitters and transducers suitable for use with tidal and coastal salt water.
- Low Range, Shallow Depth Liquid Level Sensors - Level sensors for measuring very low liquid levels in shallow rivers, weirs, drains, sewers, streams and small tanks which are immersed or mounted on the outside of a tank.
- Submersible Hydrostatic Level Sensors & Probes - Level sensors for submerging permanently in liquid to determine the level or depth of fluid by measuring the hydrostatic pressure.
- 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.
- 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.
- Marine Approved Submersible Liquid Level Sensors - Marine approval certification for use on ships. Protected from liquid ingress when completely immersed in a fluid. Device for measuring liquid level and converting it to an electrical signal to send to other instrumentation.
- 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.
- LMK458 Marine Approved Hydrostatic Level Transmitter
- LMP307 Submersible Level Transmitter
- DMK 458 Seawater Low Range Pressure Transmitter
- LMP305 Borehole Level Transmitter
- 18.605 G Low Cost Submersible Diesel Fuel and Water Tank Level Sensor
- DMP331P Hygienic Flush Pressure Transmitter
- LMK387 Cleanable Sewage and Sludge Pressure/Level Sensor
- DPT200 Pressurised Tank Level Differential Pressure Transmitter
- LMK 858 Plastic Submersible Liquid Level Sensor with Removable Cable
- LMP 308 Removable Waterproof Cable Connection Water Level Sensor
- LMK457 Marine Approved Level Transmitter
- ATM/N Titanium Submersible Hydrostatic Pressure Transmitter
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.
|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|
Related Help Pages
Browse other help pages associated with the same topic group as this Liquid Level Sensor page.