Keller Series PRD-33 X differential pressure transmitter with double sensor

Keller is launching the Series PRD-33 X, a differential pressure transmitter suitable for measuring the levels in liquefied gas tanks safely. The product has two independent sensors and measures the line pressure as well as the differential pressure.

The transmitter achieves its high accuracy level of up to ±0.05%FS due to its calibration over the entire pressure and temperature range. The mathematical model calculated in this way corrects all repeatable errors. The floating assembly of the sensor unit provides protection from external forces during installation.

The closed systems of pressure tanks require two measurements to determine the level: one for the tank pressure and one for the liquid pressure. Due to its two sensors, the product achieves this in one measurement process. All transmitter parts that come into contact with the medium are made from high-quality materials such as stainless steel AISI 316L, silicone, gold and silicon. The device is therefore suitable for use with (liquid) oxygen, argon, nitrogen, helium and carbon dioxide.

With cryogenic liquefied gases, tanks that are smaller than 3 m can have a differential pressure range of 200 mbar and a line pressure of up to 32 bar. This is overcome by the transmitter’s line pressure compensation of 0-40 bar. When the tank is being filled or the valve is being used, the tank pressure can hit one side of the differential pressure transmitter. The product copes with the resulting 32 bar uneven overloading with its overload resistance of ±35 bar.

The unit can be supplied with various electrical connections and has a digital RS485 interface that provides information such as pressure ranges, filter settings and the serial number. The supplied software enables the transmitter to be configured and controlled and data to be saved easily.