High precision pressure transmitter

• 

ZW3051GP seriesHigh precision pressure transmitterUSES the import high quality pressure sensor chip,…

ZW3051GP seriesHigh precision pressure transmitterUSES the import high quality pressure sensor chip, E2PROM chips was introduced by the built-in memory access sensors of temperature, pressure and the input/output characteristics correction parameters, then through the CPU microprocessor operation, automatic temperature compensation, signal amplifier, V/I conversion and A/D conversion, the standard 4-20 ma output signal, and A superimposed on the analog signal in accordance with the digital signal of HART protocol communication.In communications, the frequency signal of 4-20 ma signal does not produce any disturbance.As a result, the transducer has good characteristics of temperature, pressure and input/output characteristic.Can replace the ordinary pressure transmitter, widely used in petroleum, chemical, electric power, environmental protection, and other areas of the automatic detection and control.

Second, the working principle:

ZW3051GP series high precision pressure transducer principle is of two kinds of measured medium pressure ventilation with high and low pressure chamber, two effects at both sides of the components (i.e., sensitive element) isolation diaphragm, through spacer and components on both sides of the filling liquid to measure the diaphragm.Pressure transmitter is by 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.

Applications:

ZW3051GP series high precision pressure transducer 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 and absolute pressure of crystallizer, etc.

Four, the main features:

1, high precision;

2, good stability;

3, 4-20 madc two wire;

4, solid element, plug type printing circuit board;

5, small, light weight, strong earthquake;

6, continuous tunable range, zero external;

7, positive transfer of 500%;Negative transfer of 600%;

8, damping adjustable;

9, one-way overload protection characteristics;

10, no mechanical moving parts maintenance work less;

11, the structure of the whole series of unified, strong parts interchangeability;

12, optional contact medium diaphragm material (316 l, TAN, HAAS - C, MONEL and other corrosion resistant material);

13, explosion-proof structure, all-weather use;

14, intelligent HART fieldbus protocol.

Five, the performance parameters:

1, use object: liquid, gas and steam;

2, measuring range: 0-0.06 kPa to 0 to 40 mpa;

3, the output signal: 4-20 ma DC;

4, 12-45 VDC, general is 24 VDC;

5, load characteristic: related to the power supply, load ability in the era of a power supply voltage (load), RL load impedance and voltage VS relation is: RL (v - 12) or less;

6, indicator: LCD or LFD digital tube display.

7, explosion proof: flameproof dIIBT4 b: intrinsically safe iaIICT6;

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 100% of the measurement range limit (intelligent: range than 15:1) the most-positive migration amount 500% of the smallest calibration range;The largest amount of negative transfer of 600% of the minimum working range;

Working temperature range, temperature range: 10 amplifier: - 29 ~ + 93 ℃ (LT is 25 ~ + 70 ℃) pump silicone oil measuring element: - 40 ~ + 104 ℃ when the pump flange transmitter high temperature silicone oil: + 15 ~ + 315 ℃, normal silicone oil: - 40 ~ + 149 ℃;

11, the static pressure: 1, 4, 10, 25, 32 mpa;

12, the temperature, relative humidity of 0 ~ 100% RH.

13, volume variation: < 0.16 cm3;

14, damping (step response) : silicone oil filling, generally between 0.2 s to 1.67 s continuous adjustable.

Six, the technical parameters:

(without migration, in standard working conditions, silicone oil, 316 stainless steel isolation diaphragm);

1, accuracy: + / - 0.075% (0 intelligent), plus or minus 0.1% (smart), plus or minus 0.25%, plus or minus 0.5%;

2, dead zone: no (0.1%) or less;

No more than 3, stability: six months the basic error of the absolute value of maximum range;

4, vibration impact: on any axis, the vibration frequency of 200 hz;

5, power supply: less than 0.005% of output range V.

6, the load effects: power if stability, the load has no effect;

7, installation location: the biggest can produce 0.24 kPa zero error.

Other:

1, isolating diaphragm: 316 stainless steel, hartz alloy C - 276, monel alloy, titanium or tantalum;

2, vent/drain valve: 316 stainless steel;

3, flange and fittings: 316 stainless steel;

4, contact medium "O" ring: nitrile rubber, fluorine rubber;

5, pouring liquid: silicone oil or inert;

6, bolt: 316 l stainless steel;

7, electronic shell material: low copper aluminum alloy;

8 and pressure fittings: flange 1/4 NPT, center distance of 54 mm;1 1/2 NPT or M20x1 joint. 5 male thread taper sealing ball, belt joint center distance, 54, 57.2 50.8 mm;

9, signal wiring hole: G1/2.

Seven, installation requirements:

1, before installation, please read carefully the product specification, and check the related information of the product.

2, the transmitter shall be installed in ventilated, dry, no corrosion, shady and cool place, such as outdoor installation should add protective cover, avoid sun and rain, avoid transmitter performance degradation or failure.

3, the transmitter is a precision instrument, avoid strong shocks, throw during installation.

4, according to the wiring diagram properly connected.

5, pay attention to protect transmitter which leads to the cable.When used in industry site, it is recommended to use metal protection or overhead.Do not loose cable leads to the sealing nut, to avoid moisture to enter.

Eight, 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 the measurement result, should pay attention to consider 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, 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 intelligent 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 100%. 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.

Ten, selection of code:

Eleven, design selection and ordering information:

1, ZW3051GP series high precision 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, differential pressure transmitter to match three valve group, the throttle device, need to be indicated separately.

5, transducer based on 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.

6, 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.