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Magnetostrictive level transmitter
Image courtesy Jogler, LLC |
Physical properties of certain materials can be applied using ingenuity and creativity to create useful appliances. Magnetostriction, a physical property of ferromagnetic materials, produces a change in shape or dimension in the subject material when it is magnetized. This basic principle is integrated into a liquid level transmitter by extending a sensing wire along the interior length of a tube immersed in a process tank or other vessel containing the liquid to be measured. The transmitter pulses the sensing wire with an electrical current, creating an electromagnetic field. A magnetic float, travelling along the outside of the sensing tube, rises and falls as the liquid level in the tank changes. As the float moves along the length of the sensing tube, it creates a torsional stress in the sensing wire, starting at the position of the float, which matches the level of liquid in the tank. A sensing element converts the torsional stress in the wire to an electrical pulse. The transmitter measures the time differential between the initial pulse it sent down the sensor wire and the pulse resulting from the torsional stress and then calculates the position of the float and the liquid level.
These devices are very accurate and operate on a standard 2-wire loop. There are numerous options and variants that allow configuration for each application.
More information is included in the data sheet below. Your best source for current product and application information is a
product specialist. Combining your process knowledge with their application expertise will produce the best outcomes.
