High-precision absolute pressure transmitter

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ZW3051AP seriesHigh-precision absolute pressure transmitterCan realize the degassing system, distill…

ZW3051AP seriesHigh-precision absolute pressure transmitterCan realize the degassing system, distillation tower, evaporator and mold of absolute pressure measurement, such as allowed under 10 mpa overvoltage.Using the object: liquid, gas, and steam.Due to the aircraft appearance on the total integration of the current domestic zui is popular, and widely used two kinds of transducer (3051 with yokogawa EJA rosemount) the structure of the advantages, for the users to have the feeling that find everything new and fresh, at the same time with the traditional 1151, CECC, etc. Series of products can be directly replace on installation, 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:

ZW3051AP series high precision absolute pressure transmitter of the two kinds of measured medium pressure ventilation with high and low pressure chamber, two role in the delta components (i.e., sensitive element) on both sides of the isolation 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:

ZW3051AP series high precision absolute pressure transmitter on one side of the accept absolute pressure signal being measured, the other side is closed as benchmark high vacuum chamber, and then convert them into 4 ~ 20 ma. DC signal output.It can measure the degassing 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, 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.

Eight, installation requirements and precautions:

1, 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, otherwise will reduce transmitter performance or malfunction.

2, pressure transmitter using interface thread (the standard configuration of M20 x 1.5) directly installed on the system under test or the walls of the vessel where don't have to use the mounting bracket.Product pressure interface (standard) with seal groove, the measured pressure is bigger, can guarantee good sealing gasket with nylon or copper.

3, installing a transmitter, please note that shall make the cables and synthetic product, otherwise, will influence the protection of the products and lead to product failure.

4, zero (Z), range (S) adjustable products debugging methods: screw the bid opening there any need to adjust the parameters of the screw, with a small screwdriver into the among them, gently turn the adjustable resistance, and at the same time monitoring data, finish testing, tighten the screw, to avoid moisture to enter.

5, the transmitter is a precision instrument, avoid to shock when installation, throw, tightening torque should be less than 70 nm, small range transmitter (range is less than 0.5 MPa) tightening torque should be less than 14 nm. 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.

Nine, fault diagnosis:

Transducer in the measurement process, often appear some fault, fault of decision analysis and handling in time, is very important for ongoing production.We according to the experiences of the daily maintenance and some decision analysis method and the analysis process were summarized.

1, the investigation method:

Review before failure of flint, smoke, odor, power supply change, lightning, damp, wrong operation, and maintenance.

2, intuitive method:

Observation circuit of external injury, guide of pressure pipe leaking, overheating in the circuit and power supply switch state, etc.

3, test.

A, open circuit detection: separately from the rest parts of the suspected fault and to see whether the fault disappear, if lost, then determine the malfunction, or can be carried out to find the next, such as: smart differential pressure transmitter can't normal Hart, telecommunication, power supply can be disconnected from the instrument noumenon, the method of field plus a power transmitter power to communicate, to see if the cable stack 2 KHZ electromagnetic signals interfere with communication.

B, short circuit test: in the case of security, the related part of the loop short directly, such as: small difference transmitter output value, can guide tube disconnected, from a valve directly to the outside differential pressure signal directly led to the differential pressure transmitter, on both sides to observe the transmitter output, to determine the pipeline wall, leakage of connectivity.

C, replace, test: will doubt defective parts replacement, judge fault position.Such as: suspected transmitter circuit board failure, can be temporary replacement, to determine the reason.

D, division of detection: the measuring circuit of divided into several parts, such as: power supply, signal output, signal transmitting, signal detection, according to the points of inspection, by Jane to numerous, situated in, narrow range, find out the fault location.

Ten, selection of code:

Eleven, design selection and ordering information:

1, ZW3051AP absolute 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, 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.

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

7, when far eastone transmitter of choose and buy, should also be based on different remote flange selection table according to the need to be sure.

8, if remote transmitter should be used in vacuum and high temperature occasion, special label when you order.

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.