Both level differential pressure transmitters and hydrostatic level gauges are devices used to measure the level of liquids, and their main differences are in their operating principle and application.
Level differential pressure transmitter
Level differential pressure transmitters calculate the level height by measuring the pressure difference between the top and bottom of the liquid inside the container.
Differential pressure transmitters are usually available with two interfaces, one on the high voltage side and the other on the low pressure side. When the high-pressure side is attached to (or near the bottom of the vessel) and the low-pressure side is attached to the top of the vessel, the pressure difference between the two is proportional to the level height as the pressure generated by the liquid increases with depth.
It is suitable for occasions that require continuous measurement and high accuracy, such as storage tanks, reactors, etc.
They can be used to measure the level in open or sealed containers.
Hydrostatic level gauge Hydrostatic level transmitter
The hydrostatic level gauge uses the relationship between the static pressure generated by the gravity of the liquid itself and the liquid level height to measure the liquid level.
Such instruments generally have only one interface and are in direct contact with the liquid being measured. Sensitive components inside it, such as diffusion silicon or ceramic capacitors, sense the pressure of the liquid and convert it into an electrical signal output.
Hydrostatic level gauges are suitable for measuring the level in open or closed containers, but not for volatile or viscous media.
Their structure is relatively simple, easy to install, and suitable for occasions where the accuracy requirements are not particularly high but the stability requirements are high.
In summary, the main difference between a differential pressure transmitter and a hydrostatic level gauge is whether two pressure inputs are used and how the pressure information is obtained. Differential pressure transmitters offer greater accuracy and adaptability, while hydrostatic level gauges are simpler and more economical.