Intelligent pressure transmitter

Products overview:

ZW3851GP seriesIntelligent pressure transmitterIs the introduction of foreign advanced technology and equipment production of new type of transducer, the key raw materials, components and parts are imported, the whole machine after assembled and tested strictly, this product has the advanced design principle, the variety specification is complete, installation convenient use, etc.Due to the aircraft appearance on the total integration of the current domestic zui is popular, strong commonality and replace ability.For the continuous improvement of the domestic automation level and the development, this series of products in addition to the design cabinet and delicate, more has introduced HART field bus protocol of intelligent function.

Second, the working principle:

ZW3851GP series intelligent pressure transmitter is of two kinds of measured medium pressure ventilation with high and low pressure chamber, two functions in the delta components (i.e., sensitive element) on either side of the segregation on the diaphragm, through spacer and components on both sides of the filling liquid to measure the diaphragm.Measuring diaphragm and on both sides of the insulation on the electrodes of a capacitor.When we have different pressure on both sides, to cause measuring diaphragm displacement, the displacement and stress is directly proportional to the difference, so both sides capacitance range, through the link of oscillation and demodulation, is converted into is proportional to the pressure signal.And the principle of absolute and differential pressure transmitter is the same, the difference is low pressure chamber pressure is atmospheric pressure or vacuum.

Applications:

ZW3851GP series intelligent pressure transmitter is mainly used for measuring gas, liquid and steam parameters such as pressure, absolute pressure and negative pressure, and then convert them into 4-20 ma. DC signal output.It can measure the exhaust system, distillation tower, evaporator pressure and mould.

Four, the main features:

1, the super performance measurement for pressure, differential pressure, liquid level, flow measurement;

2, digital precision: + (-) 0.05%;

3, stability: 0.25% 60 months;

4, range: 100:1;

5, measuring rate: 0.2 S;

6, miniaturization (2.4 kg) stainless steel flange, easy to install;

7, process connection compatible with other products, the realization of measurement;

8, the world's only USES the H alloy sheath of sensors (technology), achieved good cold and hot stability;

9, 16 computer;

10, standard 4-20 ma, with digital signal based on HART protocol, the remote control support to field bus and upgrade based on the technology of field control.

Five, the technical parameters:

1, use object: liquid, gas and steam;

2, measuring range: 0-7000 to 40000 kpa;

3, the output signal: 4 ~ 20 ma DC (special for four wire system);220 v AC power supply, 0 ~ 10 ma DC output;

4, power supply: 12 ~ 45 v DC, general is 24 v DC;

5, load characteristic: related to the power supply, when a power supply voltage on load capacity;RL load impedance and voltage Vs relation is: RL 50 or less (v - 12);

6, indicator: pointer linear indication 0 ~ 99% scale and the LCD liquid crystal display;

7, explosion-proof grade: a: flameproof (Exd Ⅱ BT5 or Exd Ⅱ CT6);B: this Ann model (Exia Ⅱ CT6 or Ex ib Ⅱ CT6);

8, range and zero: external continuous adjustable;

9, plus or minus migration: zero after positive transfer and negative transfer, range, measurement range, of the absolute value of the upper limit and lower limit are less than 99% of the measurement range limit.Zui dazheng zui small adjustment range migration quantity of 500%;Zui large amount of negative transfer of zui small adjustment range of 600%;

10, temperature range: operating temperature range: - 20 ~ + 88 ℃;

Six, when will know parameters:

Pressure transmitter is used to measure the liquid level of liquid, gas or steam, density and pressure, and then into 4 ~ 20 ma DC signal output.And pressure transmitter with HART hａnd operator mutual communication, through it to set, monitor or with upper unit into the scene monitoring system.Buying pressure transmitter must know the following parameters.

1, the liquid material

We want to consider is the measured medium pressure transmitter, the average pressure transmitter in contact with the medium part adopts 316 stainless steel, if you're not corrosive medium of 316 stainless steel, so basically all the pressure transmitter is suitable for you of medium pressure measurement.

If you have corrosive medium of 316 stainless steel, so we're going to use chemical seal, such not only can measure the medium pressure, and can effectively prevent the medium liquid part of the contact with the contact of the pressure transmitter, thus protect pressure transmitter, prolong the service life of pressure transmitter.

2, precision grade

Every kind of electronic meter accuracy, the accuracy grade marked but because of each country is different, for example, China and the United States and other countries mark was part of the sensor in the linearity, precision and is what we usually call the precision of the measurement range of between 10% and 90%;And European targets precision is linearity of bad parts, also is what we usually call measurements of 0 to 10% and the accuracy of between 90% and 99%. Such as the European target accuracy is 1%, the target accuracy is 0.5% in China.

3, range

General sensor zui large range for sensors to the full range of 70%, which is to measure the pressure of 70 bar now, we choose the range of pressure transmitter should choose 100 bar.

4, the output signal

At this stage because of the various acquisition, pressure transmitter output signal on the current market there are many, the main 4 ~ 20 ma, 0 to 20 ma, 0 ~ 10 v, 0 ~ 5 v, etc., which are frequently used but is 4 ~ 20 ma and 0 ~ 10 v, in my above for the output signal, only 4 ~ 20 ma for two wire (what we call the output for some wire system does not contain grounded or shielded wire), other are all three wire system.

5, medium temperature

Because of the pressure transmitter signal is through the electronic circuit part of the transformation, so in general, the measurement of pressure transmitter medium temperature for 30 to + 100 degrees, if the temperature is too high, we usually use is condensing cooling medium, to such relative manufacturers have come to make sure your production a high temperature resistant pressure transmitter would reduce the cost a lot.

6, measuring medium

Usually we measure is relatively clean fluid, we adopt the standard pressure transmitter directly is ok, if you are the measured medium is easy to be crystallized or sticky, we usually use is external diaphragm or and chemical seal use together, it will effectively prevent plug hole measuring pressure of medium.

Seven, matters needing attention in use:

Pressure sensor points in the process of using, transmitter in the correct installation position on process piping and the measured medium, to effect have to measure the fruit, consideration should be paid attention to the following situations:

1, guide pressure pipe shall be installed where the temperature fluctuations small;

2, measuring, liquid pressure transmitter installation location should avoid the impact of the fluid (water hammer), in order to avoid the sensor damage of overpressure.

3, prevent the dross in intraductal deposition;

4, measuring the liquid pressure, pressure pipe side should be open in the process, in order to avoid precipitation product residue.

5 and freezing in winter, when installed in the outdoor anti-freezing measures needed for transmitter, without pressure, fluid due to the icing volume expansion in the mouth, lead to the damage of sensors.

6, to prevent the transmitter contact with corrosive or overheating of medium;

7, connection, cable through the waterproof connector (attachment) or round tube and screw down the sealing nut, such as in case of rain through the cable leakage into the transmitter inside the shell.

8, measuring, steam or other high temperature medium to connect with the buffer tube (coil) such as condenser, should not make the transmitter operating temperature more than limit.

9, measuring gas pressure, the pressure mouth should be open at the top of the process piping, and the upper transmitter should be installed in the process, so that the accumulated liquid injection process pipeline easily.

Nine, selection of code:

Ten, design selection and ordering information:

1, ZW3851GP series pressure transmitter type according to the selection of specification table according to the need to make sure.

2, selection of specifications in the table Numbers, symbols must be fill in clear, accurate.

3, if you have positive and negative migration, must indicate the migration amount value.

4, according to the user specified range checking.If the user has no rules, set at maximum range in the transmitter, the check will be carried out under room temperature and atmospheric pressure.

5, need labeling station number, should be indicated when ordering.

After-sales service commitment:

1, our company sold by pressure transmitter series products within twelve months appear quality problem, is responsible for free maintenance.

2, the warranty period, any quality problems such as the products of our company, my company is responsible for free repair or replacement.

3, the warranty period, such as user improper use, damaged products, my company is responsible for the maintenance, charge damage parts cost.

4, after the warranty period appear quality problem, my company is responsible for the maintenance, charge damage parts cost.

5, such as user need to my company site services, to users in the province I company service personnel to reach the site within 12 hours, fujian association of foreign languages and user reach the site within 48 hours.