Absolute Pressure Transmitter , Double Chamber Differential Pressure Transmitter

Double Chamber Structure Can Measure Absolute Pressure And Absolute Pressure Differential Pressure Transmitter

An absolute pressure differential transmitter is essentially a differential pressure transmitter, but its low-pressure side (reference end) is permanently sealed and evacuated to a high vacuum, forming an absolute pressure reference benchmark.

1. Core Sensor: Utilizes piezoresistive, capacitive, or resonant sensors. The sensor diaphragm senses the pressure on both the H side and the L side.
2. Key Process: During manufacturing, the reference cavity on the low-pressure side (L) is evacuated and permanently sealed. This vacuum cavity serves as the "absolute zero pressure" reference point.
3. Measurement Process: The process pressure acts on the high-pressure side (H) diaphragm and is compared with the vacuum reference on the low-pressure side (L). The sensor directly outputs a signal proportional to the absolute pressure at the H side.

The absolute pressure differential transmitter is a functionally specific but extremely useful "variant" in the family of differential pressure transmitters. It ingeniously utilizes the dual-chamber structure of the differential pressure transmitter by "fixing" one end at absolute zero, thereby achieving the function of absolute pressure measurement.