Questions and answers about liquid level measurement.
Level switch vs transmitter
What is the difference between a level switch and a level transmitter?
A switch will turn on or off at a predetermined liquid level, perhaps to protect a tank from overflowing or to maintain a minimum / maximum level in the tank. The switch output is typically either a voltage free contact or if it is an electronic switch, a fixed voltage e.g. 12 volts when ON and 0 volts when OFF.
A transmitter has a variable output signal, 4 to 20 milliamps current loop is the most common. e.g. level transmitter for a 10 metre high tank, will read 4mA if the tanks is empty, 12mA if half full and 20mA if full.
Featured liquid level measurement products
LMK458 Marine Approved Hydrostatic Level Transmitter - Marine approved level transmitter with 4-20mA output for measuring level of contents inside ship ballast, fuel, liquid cargo or wastewater tanks
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.
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Related Technical Terms
- Capacitive Fluid Level Measurement
- cmH2O – Centimetres of Water Column at 4 deg C Pressure Unit
- Conductive Fluid Level Detection
- Float Fluid Level Detection
- ftH2O – Feet of Water Column at 4 deg C Pressure Unit
- mH2O – Metres of Water Gauge at 4 deg C Pressure Unit
- mmH2O – Millimetres of Water Column at 4 deg C Pressure Unit
- Specific Gravity
- Vibrating Tuning Fork Fluid Level Detection
Related Online Tools
- Liquid Level to Hydrostatic Pressure Calculator
- Fluid Depth, Density, Gravity, and Pressure Calculator
- Liquid Level Transmitter 4-20mA Current Output Calculator
- Vertical Cylindrical Shaped Tank Contents Calculator
- Horizontal Cylindrical Shaped Tank Contents Calculator
- Rectangular Shaped Tank Contents Calculator
- Pressure to Liquid Level Calculator
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Related Application Questions and Answers
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