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.
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.
Hydrostatic Level Sensors - Hydrostatic pressure sensing devices for measuring liquid 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. 
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.
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.
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.
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.
Landfill Site Leachate Level Transmitters - Sensing transmitter devices for measuring leachate level and converting it to a 4-20mA current output signal to send to other instrumentation on a landfill site used to bury waste material.
Submersible Leachate Level Transmitters - Sensing transmitter devices protected from liquid ingress when completely immersed in a leachate for measuring leachate level and converting it to a 4-20mA current output signal to send to other instrumentation.- Landfill Site Submersible Leachate Level Transmitters - Sensing transmitter devices protected from liquid ingress when completely immersed in a leachate for measuring leachate level and converting it to a 4-20mA current output signal to send to other instrumentation on a landfill site used to bury waste material.
IWSL Potable Water Submersible Level Sensor- 18.605 G Low Cost Submersible Diesel Fuel and Water Tank Level Sensor
DS200 Combined Hydrostatic Level Switch, Gauge and Sensor
LMK809 Plastic Submersible Low Level Transmitter
LMK807 Plastic Submersible Level Transmitter
LMK 806 Plastic 21mm diameter Submersible Level Probe
LMP 308 Removable Waterproof Cable Connection Water Level Sensor- LMK351 High Overpressure Flush Level Transmitter
- IMSTL IP68 Water Temperature and Depth Transmitter
LMP307 Submersible Level Transmitter
LMK458 Marine Approved Hydrostatic Level Transmitter
DMK 458 Seawater Low Range Pressure Transmitter
- BMS water tank 6mH2Og range 0-10V out submersible level sensor
- Underground rain water storage tank level sensor and readout for 2 metre depth
- Underwater 50 metre sea depth 4-20mA output sensor
- Borewell water level sensor for 100m water height
- 200m deep well pump water level sensor, switch & display
- Arduino UNO compatible borehole water level sensor
- SDI-12 near shore tide gauge submersible 20m level probe
- Plastic seawater depth probe with 20ft range & 4-20mA out
- Swimming pool submersible pressure transmitter with 300 mbar range
- Sulfuric acid 12-15% conc. drop-in level probe for 10m high tank
- Ferric Chloride solution hydrostatic level transmitter
- 10m high chemical tank 4-20mA output submersible PVC and ceramic protected liquid level sensor
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 |
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