Hi ZIMO
请看他们的区别:

The differential voltage output of the sensor is directly
proportional to the differential pressure applied.
The absolute sensor has a built-in reference vacuum. The
output voltage will decrease as vacuum, relative to ambient,
is drawn on the pressure (P1) side.
The output voltage of the differential or gauge sensor
increases with increasing pressure applied to the pressure
希望能帮到您!
多谢!