Digital display pressure transmitter

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ZW308 seriesDigital display pressure transmitterUsing the computer automatic testing and the process…

ZW308 seriesDigital display pressure transmitterUsing the computer automatic testing and the process of laser trimming resistor to a wide range of zero and sensitivity temperature compensation with stainless steel OEM metal seal diaphragm of pressure resistance sensor as the signal measuring element, the sensor signal after the signal processing circuit is converted into a standard signal output, product after long term aging and stability assessment process strict screening, such as stable and reliable performance.

Second, the working principle:

ZW308 series digital display pressure transmitter is when the pressure on the diaphragm, resistance to change and produce a linearization is proportional to the applied pressure of the output signal.With dc power supply, will produce a dc voltage signal output.After a second crossover, realizes the two wire system 4 ~ 20 ma output.

Applications:

ZW308 series digital display pressure transmitter is reliable industrial measurement and control equipment.Widely used in petroleum, chemical, electric power, environmental protection, water treatment, automation equipment, such as monitoring pressure, according to the process control field.Has good characteristics of temperature, pressure and input/output characteristic.Suitable for bad environment gas, liquid pressure measurement and control.

Four, the main features:

1, good stability, full, zero long-term stability can amount to 0.2% FS/year.Within the scope of the compensation temperature 0 ~ 70 ℃, the temperature drift less than 0.2% FS, throughout the allowed working temperature range is less than 0.5% FS.

2, with reverse protection, current limiting protection circuit, when the installation is negative answer the reverse will not damage the transmitter, abnormal transmitter automatically when current limit within 35 ma.

3, solid structure, no moving parts, high reliability, long service life.

4, from wind to water, oil can be high precision measurement, not affected by the quality of the measured medium size.

5, easy installation, simple structure, economy is durable.

Five, the technical parameters:

1, power: 24 VDC output 4 ~ 20 ma two wire;

2, zero adjustable scope: plus or minus 5% f. S.

3, range adjustment than: 3:1 above;

4, range range: - 100 kpa ~ 0 ~ 60 mpa;

5, load characteristics, load within 0 ~ 600 Ω (24 VDC power supply) to maintain constant current output;

6, flameproof: d Ⅱ BT4, the Ann model: ia Ⅱ CT5;

7, overvoltage limit: 2 times the upper limit pressure;

8, temperature range: process: - 20 ~ 60 ℃;

9, precision grade: + / - 0.5%;

10 and stability: plus or minus 0.2% f. S.

11, weight: about 1 kg.

Six, when ordering explosion-proof transmitter must pay attention to several items:

1, the transmitter explosion-proof products have two type flameproof and intrinsically safe;

2, make clear the site for the dangerous sites of flammable and explosive medium composition and places;

3, please select explosion-proof grade than flammable medium level and high humidity group or the same transmitter.

4, explosion-proof products allows the use of the environment temperature is 20 ℃ ~ + 70 ℃. -

5, when ordering intrinsically safe transmitter, must according to the nameplate and manual requirements, purchase the corresponding safety barrier and cable as required.

Seven, install and use notice:

1, read carefully over goods packaging product manuals.Correct connection circuit according to drawing.Especially pay attention to the connection error transmitter products may not be.

2, threaded connection products during installation and removal, must use wrench screw nut, cannot twist too tight when installation, it is strictly prohibited to other clamping parts, installation, disassembly, avoid damage related connection parts.Bring pressure Kong Duan shall not have sharp hard to reach, in order to avoid damage sensitive film or isolation membrane, it is strictly prohibited to knock, bump, it broke down.

3, products specifications, packing list, the certificate should be properly kept, it is the basis of three packs.

4, product appearance, and shall be randomly pick stitching thread processing, modification, or accept the responsibility for quality problem.

Overload 5, prohibit super, super sensitive membrane damage index overload is not in the warranty scope.

Attention should be paid to the following several kinds of usage:

A, be a larger pressure system transient overload pressure.

B, pressure test, pressure equipment such as pump head is too big, strong pressure, liquid level high speed impact diaphragm sensitive membrane, big impact momentum with pressure overload.

C, with the piston pressure gauge calibration, the piston failure stuck not found that cause stress made the high overload impact sensitive membrane.

6, due to the constant current power supply since the compensation function of diffused silicon sensor, constant current source is recommended for the power supply in principle, our company can also provide a constant sense of circulating integration products, such as measuring temperature coefficient of request is not high, conditions are not allowed to, also can use constant voltage source.

7, diffusion silicon sensor zero output cannot be directly using single arm al resistance method to eliminate, the software can be used to zero method, differential input shaping method, T resistance network modification, etc.

8, it is forbidden to use sharp hard objects, screwdriver, finger press wax directly testing, zui so likely to cause irreparable damage, silicon membrane or isolation membrane damage (direct consequence of the excess pressure overload or pressure to the products caused by zero greaten, failure, is beyond the scope of warranty.

Eight, common fault handling:

1, when installation should keep transducer pressure sensitive axis perpendicular to the direction of gravity, if the installation conditions, you should adjust the transducer zero after installation fixed to the standard values.

2, residual pressure relief not to come out, so the sensor's zero come down again.Rule out the reason for this ideal method is to remove the sensor, direct look at zero is normal, if zero normal replacement of sealing ring to try again.

Three output does not change, pressure transmitter, pressure transmitter output again suddenly changes, pressure transmitter zero return not to go.The reasons for this phenomenon is likely caused by pressure sensor seal ring.

4, whether to conform to the requirements of the power supply;The power and presence of wrong wiring between transducer and load equipment.If there is no voltage or polarity reverse of transmitter terminals can cause transmitter no voltage signal output.

5, pressure sensor and transmitter shell generally need grounding, signal cable shall not be mixed with the power cable laying, sensor and transmitter there should avoid strong electromagnetic interference.Sensor and transmitter in use should be periodic verification as stipulated in the industry.

6, users in the selection pressure sensor and transmitter, should fully understand the condition of pressure measurement system, reasonable choice according to need, make the system work in ideal state, and can reduce the engineering cost.

7, 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.

Check once a week 8, pressure transmitter, requirement, inspection once a month, main is to clear the dust inside the instrument, the electrical components inspection earnestly, the output current value always proofread, internal pressure transmitter is low, must be separated from high voltage with the outside world.

Eight, selection of code:

Nine, design selection and ordering information:

1, the sensor material;

2, explosion-proof situations;

3, connecting head materials and connection mode;

4, seal materials;

5, precision;

6, range scope;

7, whether or not to bring additional options.

After-sales service commitment:

1, our company sold 308 series product quality problem within 12 months, 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.