The anti-corrosion capacitive liquid level transmitter

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Anticorrosion capacitive liquid level transmitter is a kind of can be used in corrosive liquid, oil,…

Products overview:

ZW - DBF702 seriesThe anti-corrosion capacitive liquid level transmitterIs to use detection sensor rods, wall insulation and barrel (of electrode) to the capacitance between reactants, when medium induction rods were covered, the capacitance between the two level changes, then when preset limit is reached, the output switch signal to realize the material level detection and remote control, its structure is simple, no mechanical transmission structure, performance is stable and reliable, suitable for all kinds of solid and liquid materials.

Second, the working principle:

ZW - DBF702 series anti-corrosion capacitive liquid level transmitter is measured by the change of capacitance level, probe and made of conductive material in the container wall consists of a capacitor.For two given electrode (given probe and a given container) and capacitance consisting of measured medium, to motivate, with fixed frequency voltage when process dielectric constant of dielectric constant, the size of the current through the capacitor is proportional to the height of the dielectric capacitor electrodes, converting the current ma 4-20 ma output, thus the output of the transducer is proportional to the height of the container material level.The relative dielectric constant of general process medium should be above 1.5.

Applications:

ZW - DBF702 series anticorrosive capacitive liquid level transmitter is suitable for high temperature and high pressure, strong corrosion, easy to crystallization, easily blocked harsh conditions such as continuous detection of various liquids.Suitable for measuring water, acid and alkali solution, and the boiler water level, the whole machine there or elastic parts, impact resistance, easy installation, high reliability and high precision.Alternative to traditional ball float, the type of investment and the differential pressure type liquid level transducer applied in all kinds of situation.

Four, the main features:

There were 1, simple structure, moving or elastic components, so the reliability is extremely high, little maintenance.In general, don't have to do regular large, medium and small maintenance.

2, a variety of signal output, convenient for different system configurations.

3, suitable for high temperature and high pressure container level measurement, and the measured value is not affected by the temperature of the liquid to be tested, proportion, and the shape of the container, pressure influence.

4, especially suitable for the measurement of strong corrosive liquid such as acid, alkali.

5, perfect over-current, over-voltage, power supply polarity protection.

Five, the technical parameters:

1, the detection range: 0.01 ~ 5 m;

2, fine degree: 0.2, 0.5;

3, pressure range: 0.1 MPa ~ 32 MPa;

4, agent and heat-resistant: - 50 ~ 250 ℃;

5, ground pole diameter: Φ 8;

6, the environment temperature: - 20 ~ 60 ℃;

7, storage temperature: 55 ℃ ~ + 125 ℃;

8, the output signal: 4 ~ 20 ma, 4 ~ 20 ma superposition HART communication, 485 communication, CAN bus communication;

9, the power supply voltage: 12 ~ 28 VDC (subject to security grid power supply);

10, fixed way: thread M20 x 1.5 installation, M27 x 2,

Flange installation DN25, DN40, (.Special specifications can be customized according to the requirement;

11, wet material: stainless steel, 316 1 gr18ni19ti or ptfe;

12, long-term stability: 0.2% FS/year or less;

13, temperature drift: 0.02% FS / ℃ or less (within 0 ~ 70 ℃);

14, explosion-proof grade: this Ann Exia Ⅱ C T6 flame-proof Exd Ⅱ C T5;

15, protection grade: IP67.

Six, installation and commissioning:

Cable type and lever type liquid level transmitter has many installation fixed way, so as to adapt to different site conditions.When the site will not be able to provide M20 x 1.5 in the process facilities such as thread or the flange, can choose wall installation type, horizontal pipe frame and vertical posture, such as three optional installation way, make you comfortable when installation.

When measuring liquidity larger medium, to prevent violent oscillation sensor, the user can choose counterweight attachment, to have the effect of stable sensors, add weight must to put weight objects in the bottom of the container, in order to avoid pull bad sensing wires.

In the field environment is bad, the user should choose sensor shield to protect sensor, to avoid the foreign body damage or affect the accuracy of measurement.

Using ZW702 lever type liquid level transmitter, if not metal containers, you need to put the transmitter of the shell with a wire access the bottom of the container, otherwise not accurate measurement.

This product in the factory has a calibration, if need on-site adjustment can adopt the following methods:

A: using intelligent circuit debugging methods:

The zero -- -- -- -- -- - when the liquid level position is low, at the same time hold down the "Z" key and "S" key 8 seconds after release at the same time, then "Z" key press, the output current automatically adjusts to 4 ma.

Field adjustable full -- -- -- -- -- - when the liquid level high, at the same time hold down the "Z" key and "S" key 8 seconds after release at the same time, then the "S" key press, automatic adjustment to 20 ma output current.

B: adopting the method of analog circuit debugging:

When the liquid level in the next period, use the screwdriver slowly rotating "Z" potentiometer, observe the ammeter reading close to 4 ma.

When the liquid level in the limited time, use a screwdriver slow rotation "S" potentiometer, observe 20 ma current meter reading is close.

So above 2 to 3 times repeatedly, until zero and range are accurate 20 ma ma and 4, respectively.

After adjust, should tighten the lid of the transmitter.

Seven, installation and the matters needing attention:

Appearance and installation:

Liquid level transmitter consists of shell, amplifier, terminal blocks, helmets, hollow wire, etc, according to the needs of the user can choose a pointer table, LCD display meter.

Installation method:

1, choose easy to place for installation operation and maintenance;

2, shall be installed as far as possible away from the vibration source;

3, should be far away from heat source as far as possible;

4, the inputting type liquid level transmitter installation, metal probe to sink to the bottom of the container.

Note:

1, the supply of products with product certificate and instruction manual with the product serial number, technical parameters, wiring diagram, production date, etc. Please check carefully to avoid using wrong.

2, when installation should be according to the product connection and screw type, check the site interface is consistent with the product interface.For screw thread interface, should slow tightened, pay attention to the sealing, can't add the torque directly to the transmitter shell, can only add on the six-party transducer interface.

3, connection should be in strict accordance with the company I use for connection.

4, this product is a precision in instrument, banned free disassembly, collision, drop, play hard.

5, the transmitter power can work, but warm up 30 minutes output stability.

6, if discovery is unusual, in use should turn off the power and stop using, check, or directly to our technical department.

7 should be restored the original packaging, transportation, storage, stored in a cool, dry and ventilated warehouse.

8, installation and use process should pay attention to not put the induction of the skin of the wire broken.

9, when installation induction leads to at least more than 10 cm away from the pool wall, otherwise not accurate measurement.

10, all four fluorine structure and lever type level ground wire must be measured medium conduction, and measurements are not accurate.

11, installation site should take effective lightning protection measures.

12, the series of any liquid level transmitter enclosure must be reliable grounding, grounding resistance should be less than 4 Ω.

13, according to the security gate flame-proof certification, its installation should be according to the requirements of the specification.

14, when the transmitter is used to "0" zone, grid power supply to the safety of the power transformer shall meet the requirements of article 8.1 GB3836.4-2000.

Eight, selection of details:

1, indicate the measuring range (level of), for some special medium, indicate the density of the medium.

2, type selection, attention should be paid to contact with the product of the measured medium material compatibility, for special medium, can be customized.

More than 3, the product installation in the thunderstorm area, the order should be marked "lightning", recommend that users install against lightning protection device at the scene, and make sure products and power grounding.

4, about the selection of gas leading cable length: general than the actual level of 1 ~ 2 meters long.

Nine, measuring system:

Measurement system for this type.

This safety type pressure, differential pressure transmitter adopts the intrinsically safe circuit, suitable for explosion-proof grade ExiallCT4 - CT6 explosion danger area.

Shielding signal cable must be used in the system circuit, and reliable grounding.Below are just 4-20 ma output signal and the measurement system of 0 to 10 ma, for example the wiring diagram,

Liquid level transmitter has reliable operation, stable performance, small volume, light weight, low cost, refined design, a variety of structural form, easy installation, without stents.Circuit board USES the microprocessor based electronic technology, can automatically eliminate the influence of temperature change on the sensor precision.

This series of products can be equipped with LCD liquid crystal display (LCD), to facilitate the local operation.

Intelligent output with HART communication function at the same time.

Ten, selection of code:

Twelve, design selection and ordering information:

1, model specifications: ZW - DBF700 series;

2, the name of the measured medium, medium density;

3, instrument measuring range: can also be referred to as the nominal length;

4, work pressure, work under pressure;

5, working temperature: measuring the temperature of the liquid;

6, material requirements: liquid material;

7, whether matching supply flange, bolts, nuts, valves, fittings, such as sealing washer;

8, flange standard: nominal size of the flange, 3/4 ", DN25, (, DN80, DN100 or 6;

9, special requirements: before ordering, please indicate in detail.

After-sales service commitment:

1, our company sold by liquid level 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.