What is it?
The SST51 is a SMART float-type level transmitter that operates using a reed-switch chain. A magnet inside the float moves with the liquid level and activates the switches without physical contact. The electronics convert these switch changes into a 4–20 mA output with HART communication. The device also includes an LCD display and allows local configuration through four push buttons.
Where is it used?
The SST51 is used in industrial tanks and process installations that require reliable, low-maintenance level measurement. Because only the float contacts the liquid and the electronics remain isolated, it is suitable for corrosive, clean, contaminated, or variable process conditions. With ATEX approval, it is also suitable for hazardous areas (Zones 0, 1, and 2).
3. How does it work?
As the liquid level rises or falls, the magnetic float travels along a guide tube. This movement changes the state of the reed switches inside the tube. The electronics read these switch transitions and apply automatic temperature compensation using an integrated PTC sensor. A microprocessor converts the measured level into a 4–20 mA two-wire output and displays the reading on the LCD.
What problems does it solve?
The SST51 eliminates many issues associated with traditional level sensors that are fully submerged in liquid, such as corrosion, fouling, mechanical wear, and performance changes due to liquid properties. It provides a stable, accurate, and low-maintenance measurement even under changing temperature and process conditions thanks to automatic drift compensation. The addition of HART communication allows both local and remote configuration, reducing installation time and maintenance effort.
