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Pressure transmitter manual

Apr 08, 2019


Pressure transmitter manual


1 Overview

The diffusion silicon pressure transmitter produced by our company adopts a new generation of pressure detection principle. Compared with traditional products, it has advanced technology, reliable performance, convenient installation, high precision, small volume and vibration resistance. It has become the most used pressure transmitter in the field of industrial process control. According to the principle, it can be divided into intelligent type and analog type. It is suitable for pressure detection of gases, liquids and vapors in chemical, petroleum, power, metallurgy, building materials, medicine, food, water supply and drainage, and converts them into 4-20mADC signals. With the corresponding display instrument, recording instrument or regulator, automatic monitoring of pressure parameters.

hart protocol remote seal differential pressure transmitter6

2, Main technical indicators

Use object liquid, gas or steam

Working voltage :13-45VDC

Output signal :4~20mADC

Measuring range table pressure: maximum 0~50MPa minimum 0~lkPa

Absolute pressure: maximum 0~30MPa minimum 0~20kPa

Negative pressure: -O.IMPa-IMPa Range ratio 20: 1 (smart type) 4 : 1 (analog type)

Overload range is better than 2 times the factory range

Accuracy class 0.1 level 0.2

Temperature effect 0.25% FS/10'C stability better than 0.2% FS/year

Position influence: the installation position zero point affects less than 20Pa

Allowable temperature: normal operating temperature: -25 ° C -85X:

(LCD operating temperature range: -25^~70^)

Storage temperature: -25X: -85 C Relative humidity 0~95%RH

Material with degree of protection IP65 in contact with the measured medium

process connection: 316 not pound steel, Hastelloy C

Sealing parts: fluororubber, nitrile rubber, PTFE. The wiring connector is a universal cable connector M20x 1.5.

 

3, Installation and use

The accuracy of the measurement of the pressure depends to a large extent on the correct installation of the transmitter and the pressure piping. Transmitters for level measurement are often only installed in harsh environments, taking into account process and economic factors. However, the transmitter should be installed as far as possible in places where temperature gradients and temperature fluctuations are small, while avoiding vibration and shock.

Installation of the pressure pipe

The correct position of the transmitter relative to the process piping depends on the medium being measured. In order to choose the best installation location, the following points should be considered:

. Corrosive or overheated media cannot be in direct contact with the transmitter;

. Prevent the slag from depositing inside the pressure tube;

. Use the impulse tube as short as possible;

. The pressure piping should be installed in a place with a small temperature gradient and fluctuations;

When measuring the gas pressure, the pressure pipe should be installed on the top or side of the pipe. The transmitter should be installed above the side pressure port to allow liquid to drain into the process pipe.

When measuring the liquid pressure, the pressure piping should be installed on the side of the process piping to avoid slag deposits. The transmitter is mounted below the side pressure port for gas to be discharged into the process piping.

When measuring the steam pressure, the pressure pipe should be installed on the side of the pipe, and the transmitter should be installed below the pressure tap to allow the condensate to flow through the pipe.

When measuring steam, the pressure piping is filled with water to prevent direct contact of the steam with the transmitter.

Since the volume change of the transmitter is small, a condenser is not required.

The pipeline connecting the transmitter to the pressure port of the measured medium is the pressure transmission channel. During the pressure transmission process, the causes of the error are as follows:

.Pressure leak

. Friction loss of the pressure pipe

. Gas is accumulated in the pipeline of the liquid medium

. Accumulation of liquid in the pipeline of the gas medium

In order to keep the installed transmitter in an explosion-proof function, the following items must be observed (see the explosion-proof manual for details).

. The cover must be tightened to ensure that at least 6 snaps are engaged and the threads must not be damaged.

. The connection between the sensor and the electrical housing must be at least 6 buckles and there should be no damage to the threads.

. The wiring holes must be sealed with suitable seals.

. If another wiring hole on the housing is not used, it must be plugged with a threaded metal plug to engage at least 6 buckles.

. The sealing layer between the circuit side and the wiring side of the electrical housing must not be damaged and the terminals must be intact.