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.
Liquid level measurement products
ATEX Approved Liquid Level Sensors for Hazardous Areas- Hydrostatic Level Sensors
External Mounted Tank Level Sensors
18.605 G Low Cost Submersible Diesel Fuel and Water Tank Level Sensor