Pressure transmitter

1、 Product Overview

Pressure transmitters are used to measure the liquid level, density, and pressure of liquids, gases, or vapors, and then convert them into 4-20mA DC signal outputs. The pressure transmitter can communicate with the HART controller for setting, monitoring, or forming an on-site monitoring system with the upper computer.

2、 Working principle

The process pressure of the pressure transmitter is transmitted to the center measuring diaphragm of chamber D through the isolation diaphragm on both sides or one side, and the filling liquid. The central diaphragm is a tensioned elastic element that produces corresponding deformation displacement in response to the pressure difference acting on it on both sides. Its displacement is proportional to the differential pressure, with a displacement of about 0.1mm. This displacement transformation forms a differential capacitor on the capacitor plate, which is converted into a 4-20mA DC signal output in a two-wire system by electronic circuits.

3、 Installation skills

The installation position of pressure transmitters on process pipelines is related to the measured medium. When installing, attention should be paid to the following situations:

1. Try to avoid direct contact between the transmitter and corrosive or overheated test media.

2. To prevent debris from depositing inside the pressure pipe.

3. The pressure pipe should be as short as possible.

4. The liquid column pressure inside the pressure guiding pipes on both sides should be kept balanced.

5. The pressure conduit should be installed in a location with small temperature gradients and fluctuations. When measuring liquid flow rate, the pressure tap should be opened on the side of the process pipeline to avoid sedimentation of debris. At the same time, the transmitter should be installed next to or below the pressure tap to allow air bubbles to be discharged into the process pipeline. When measuring gas flow rate, the pressure tap should be opened at the top or side of the process pipeline. And the transmitter should be installed next to or on top of the process pipeline so that accumulated liquid can easily flow into the process pipeline.

4、 Product price

The price of pressure transmitters is related to the model, and different models have different prices. For example, 2088 diffusion silicon pressure transmitters, compact pressure transmitters, and high-temperature pressure transmitters have different prices. The final quotation should be based on the on-site working conditions and model.

5、 Product parameters