Pressure transmitters for relative and absolute pressure

Function: Changing the measured pressure will cause the sensor diaphragm to deflect. This change is converted to a 4-20 mA output signal.

Technical parameters of absolute and relative pressure sensors:

Type of measured pressure value: Relative, absolute
Accuracy: <0.5%
Output type: Analog
Analog output: 4 - 20 mA
Supply voltage: 24 VDC
Connector: Hersman DIN43650
Housing material: Stainless steel AISI 304
Membrane material: Stainless steel AISI 316
Sensor material: Silicon
Degree of protection IP: IP 65
Temperature range of the measured medium: –25 ° C ～ +8 5 ° C
Response time: 10 ms
Influence of ambient temperature: 0–50 ° C from the upper limit of the range <0.5%, –20 ° C to + 80 ℃ from the upper limit of the range <1%
Seal: Viton
Overload capacity: 150% of the measured range
Suitable for materials compatible with stainless steel AISI 304.

Another option for connecting absolute and relative pressure sensors:

Possibility of delivery with separating clamp membrane made of stainless steel AISI 316L - easy sanitization of the meter.

Use:

Light industry
Medical devices
Regulation of pressure processes
Hydraulic and air pressure systems
Cooling, air conditioning
Compressors
Food and beverage industry

Absolute pressure, relative pressure, and differential pressure

Every pressure measurement, even for example a tire pressure measurement, is related to a reference pressure. Usually, the measurement is related to the pressure of the physical atmosphere, other times it is a measurement with respect to an ideal vacuum or to another reference pressure. When measuring pressure, we, therefore, distinguish the following terms:

Absolute pressure is the pressure measured against an ideal vacuum, absolute pressure is equal to relative pressure plus atmospheric pressure.
Relative pressure is the pressure measured against atmospheric pressure, so it is equal to the difference between absolute pressure and atmospheric pressure.
Differential pressure is the pressure difference between two different points.

source: Wikipedia