1、 Range selection

The measuring range should cover the maximum differential pressure value of the tested system and reserve a safety margin. It is usually recommended to have a range of 1.5-2 times the maximum differential pressure, for example:

Filter performance testing: If the inlet pressure is 300kPa and the outlet pressure needs to be ≥ 280kPa, the differential pressure range is selected as 20kPa (300-280=20kPa).

High pressure tank consistency testing: If the standard pressure of two tanks is 1MPa and the allowable differential pressure is ≤ 1kPa, the measuring range should be selected as ± 1kPa (bidirectional measurement).

Attention: For micro differential pressure scenarios (such as clean room pressure difference), high-precision small range transmitters should be selected to avoid insufficient resolution caused by excessive range.

2、 Accuracy requirements

The accuracy needs to be determined according to the application scenario:

Industrial process control: Typically, ± 0.1% - ± 0.5% FS (full-scale accuracy) is selected, such as pressure monitoring of chemical reaction vessels.

Laboratory or precision machining: Higher precision (such as ± 0.05% FS) is optional, but the cost needs to be balanced.

Key point: Accuracy is affected by factors such as temperature, static pressure, and range ratio, and needs to be comprehensively evaluated based on actual working conditions.

3、 Media compatibility

Select materials and structures based on the characteristics of the medium:

Corrosive media (such as acidic and alkaline solutions): Choose corrosion-resistant membranes such as tantalum and Hastelloy, or use isolated transmitters (transmitting pressure through the isolation membrane and filling liquid).

High viscosity/easy to crystallize medium: Choose an insertable double flange differential pressure transmitter to avoid blockage of the pressure pipe.

High temperature medium: Choose a high-temperature transmitter (such as ceramic diaphragm), or install a condenser/siphon tube to protect the sensor.

4、 Installation method

Select installation form based on site conditions:

Straight through method: suitable for liquid/gas media, directly installed on the flowmeter to reduce the length of the pressure pipe.

Flange method: suitable for high temperature, high pressure, and corrosive media, connecting containers or pipelines through flanges.

Threaded connection type: suitable for low-pressure, small-diameter scenarios, easy to install but with high sealing requirements.

Attention: Gas media should be pressurized from the top of the pipeline first, while liquid media should be pressurized from the side or bottom to avoid the deposition of bubbles or solids.