Electromagnetic Flow Meter Installation

Introduction of Electromagnetic Flow Meter

Electromagnetic Flow Meters use the principle of Faraday’s Law of Electromagnetic Induction to measure the flow rate of a liquid in a pipe. In the pipe section of the magnetic flowmeter, a magnetic field is generated, and is transmitted to the liquid flowing through the pipe. Faraday’s law states that the resulting voltage is proportional to the movement of the flowing fluid. A conductor moving through a magnetic field produces an electrical signal within the conductor. And the singal is proportional to the speed of the water moving through the field. As a liquid flows through a magnetic field, the conductive particles in the liquid make changes. This variation is used to measure and calculate the velocity of water flow through pipes. When the fluid moves faster, more voltage is generated. The Flow Converter processes the voltage signal to determine the fluid flow.

Electromagnetic Flow Meter Components

An electromagnetic flowmeter consists of two parts, namely an electromagnetic flow sensor and an electromagnetic flow transmitter or magnetic flow converter.

Electromagnetic Flow Sensor Electromagnetic flow sensor

functions to capture flow signals based on Faraday’s law which is forwarded to the flow converter to be processed by producing the amount of flow readings on the display. Magnetic Flow Sensors use a set of coils and a pair of electrodes for flow measurement. The coil of the meter is driven by the transmitter with an applied current. Once powered, a magnetic field is formed between the two coils. When the pipe is full and the liquid begins to flow, the force of the magnetic field causes the negatively and positively charged fluid particles to separate as they pass through the magnetic field. This separation causes an induced voltage between the electrodes and the sensor.

If the direction of the magnetic field is constant, [electrochemical|electrochemical] and other effects on the electrodes will make the potential difference difficult to distinguish from the potential difference induced by fluid flow. To demonstrate this in modern magnetic flowmeters, the magnetic field is constantly reversed, eliminating the electrochemical potential difference, which does not change direction with the magnetic field. However this prevents the use of permanent magnets for magnetic flowmeters. The components of the electromagnetic flow sensor are

The components of the electromagnetic flow sensor are

• Flow tube
• Coils and electrodes
• Liners
• Cover
• Connection

Electromagnetic Flow Transmitter or Converter The electromagnetic converter in addition to providing coil current to turn on the magnetic field is also tasked with taking the voltage generated by the sensor, converting the voltage into a flow measurement and sending the flow measurement to the control system. Flow converters usually consist of displays and output components of the process in the form of pulses, output currents of 4 – 20 mA and communication in the form of harts protocol or RS485. And there are some that can provide contact alarm output and others. In terms of the electromagnetic converter power supply, DC, AC and battery power are available, depending on the needs and the type of power supply available. Likewise, in terms of installation, there are meter mounts and wall mounts. for the type of wall mount it is usually used for those who want a split or remote type electromagnetic flow meter where the display is separated from the electromagnetic flow sensor due to onsite needs.

Electromagnetic Flowmeter Installation

Are you ready to install Electromagnetic flowmeter?

Then this electromagnetic flowmeter installation guide is exactly what you need. The electromagnetic flowmeter installation instructions here apply to flowmeters in general. If you have questions about how to install and installation requirements for an electromagnetic flow meter, don’t hesitate to ask the manufacturer, so that the purpose and function of this flow meter installation can be maximized.

Electromagnetic flow meters are mainly used to measure liquids that have a conductivity that meets the requirements of Faraday’s law. An electromagnetic flow meter, also called a magnetic flowmeter or a mag meter, is a volumetric flowmeter that works on the principle of magnetic technology. Electromagnetic flowmeters have no moving or rotating sensor components so they are suitable for use with all types of liquids such as clean water, dirty water or waste water.

Basic knowledge of Electromagnetic flowmeter installation

To install an electromagnetic flow meter, the most important thing is to determine the location where the pipe is full of liquid. Such as the position of the vertical pipe with flow from the bottom up or in the position of the horizontal pipe by selecting the lowest point condition in the entire pipeline network.

In determining the installation point of the electromagnetic flow meter, avoid locations where air or liquid entrapment in the pipe is not filled with liquid. The position of the measuring point must be selected at a position greater than 10D in the upstream and 5D Downstream. The flowmeter mounting point should be selected as far as possible from pumps, valves, and other equipment. Avoid interference with measurements. The measuring point should be selected as far as possible from the source of strong magnetic field interference.

Electromagnetic Flow Meter Installation Type

Electromagnetic Flow Meters have 2 types of installation based on the connection to the pipe, namely In Line Flow Magnetic Sensor and Insertion Flow Magnetic Sensor. In Line Magnetic flow sensor, how to install it by cutting the pipe and then installing a connection in the form of a flange or thread. While the insertion electromagnetic flow sensor is installed by making a hole in the pipe, then installing a fitting either in the form of a saddle fitting or a weldod fitting to insert the electromagnetic sensor into the pipe.

The selection of the type of installation of a magnetic insertion flow meter should be used for large pipe diameters, because it will be able to reduce investment costs and installation costs and the flowmeter price will fall cheaper.

For the type of converter or electromagnetic flow transmitter, there are 2 types of installation, namely compat or integral and remote or split. For compact the converter position is integrated with the flow sensor, while for the remote converter the position is separated from the flow sensor with a distance of up to 100 m or more depending on the manufacture.

Electromagnetic flowmeter installation steps

The installation procedure of the electromagnetic flowmeter is simple.

• Make sure the type of pipe connection (flange, thread, wafer triclamp or other)
• Make sure the need and type of power supply (AC, DC or battery)
• Select the correct installation location point.
• Installation inspection. After installation, check whether the pipe is installed correctly and whether the connection is reliable, especially check the ground wire.
• Turn on to warm up. After the electromagnetic flowmeter is turned on and warmed up for 20 minutes, the electromagnetic flowmeter can normally measure normally.
• Zero tracking. To maintain the accuracy of the electromagnetic flowmeter, zero tracking is required. If the measuring tube of the electromagnetic flowmeter is filled with media, a zero point calibration can be performed and then stored (confirmed).
• Don’t forget to confirm the measurement results with the pump capacity or use portable flow meter ultrasonic.

When installing an electromagnetic flow meter, there are several things that need to be considered. Where the flow meter installation procedure must pay attention to the requirements and installation steps so that the purpose of electromagnetic flow meter installation this can be accomplished. What needs to be considered is the location of the flow meter installation because for indoor locations and installation at out door locations, adjustments need to be made.

Likewise, the installation position of the electromagnetic flow meter with respect to height, where if electromagnetic flow meter installed on pipes with a height of 3 meters or more of course different from electromagnetic flow meter installed in an underground position or in a ditch.

Important things in electromagnetic flow meter installation

• Electromagnetic flowmeters should be installed in places where the temperature changes greatly or the device is exposed to high temperature radiation. If installation is required, measures should be taken for heat insulation and ventilation.
• Electromagnetic flowmeters are best installed indoors. If it must be installed outdoors. Avoid pouring rainwater, flooding and sun exposure. Must have moisture and sun protection measures.
• Flowmeters, especially flowmeters with intelligent liquid crystal display screens, should be installed in a location protected from direct sunlight. Ambient temperature should be between 5C and 55C.
• Electromagnetic flowmeters should be avoided in environments containing corrosive gases. When installation is required, ventilation measures should be taken.
• In order to facilitate installation, maintenance and maintenance, sufficient installation space is required around the flowmeter.
• The place of installation of the electromagnetic flowmeter should avoid strong magnetic fields and sources of vibration. If the pipe has a large vibration, there should be fixed pipe supports on both sides of the flowmeter.
• Install the flowmeter in a place where there is no strong electromagnetic field radiation. Avoid devices such as electric motors, transformers, frequency converters, etc. which may cause electromagnetic interference. The measurement principle of the flow meter is based on Faraday’s law of electromagnetic induction. The original signal it produces is very weak, less than a millivolt. If there is a strong electromagnetic field radiation near the flowmeter, it will affect the measurement accuracy and may not even work properly.
• Straight pipe length. Take care to avoid eddy current generating components, such as various valves, elbows, bypasses, etc. Try to extend straight pipe sections upstream and downstream of the flow meter. Install a rectifier if necessary. Make sure the upstream of the flowmeter straight pipe is more than 5 DN (pipe diameter measurement), and the downstream is more than 2 DN.
• The conductivity of the liquid must be uniform and stable. Do not install the flow meter in a place where the conductivity of the liquid being measured is very uneven. If different media is injected upstream, it will cause uneven conductivity and affect the measurement. In this case, it is recommended to move the injection port downstream. If it has to be injected upstream, it should be kept as far away from the flow meter as possible. Generally, it is better to keep a distance of more than 20 DN to ensure the liquid is mixed evenly.
• Maintain electrode wick level. The plane of the measuring electrode must be level. This prevents short time isolation between the two electrodes due to air bubbles.
• No air bubbles. Ensure that no air bubbles are generated when the flowmeter is installed in the pipe design.
• Full pipe flowmeter. The flowmeter can be installed horizontally, vertically and at an angle. However, the pipe structure must ensure that the measuring tube is always filled with liquid (the tube is full). When designing the pipe, pay attention to ensure that there are no air bubbles in the measuring pipe section, otherwise it will cause unstable measurement and excessive deviation.
• Upstream pipe length of electromagnetic flowmeter, recommended 20D and Downstream along 5D.

Electromagnetic Flow Meter Accuracy and Calibration

The measuring principle of an electromagnetic flowmeter is Faraday’s law of electromagnetic induction. Electromagnetic flowmeters measure the flow of a conductive liquid according to the electromotive force induced when a conductive liquid passes through an external magnetic field. The main components of the sensor are: measuring tube, electrode, excitation coil, iron core and yoke case. The product is mainly used to measure the volumetric flow of conductive fluids and slurries in closed pipes, including acids, alkalis, salts and other corrosive liquids.

Electromagnetic flowmeter quick calibration:

• Select the appropriate pump according to the diameter and flow rate of the pipe to be verified;
• After the flowmeter is properly connected, it must be turned on and warmed up for about 30 minutes according to the requirements of the verification regulations;
• If a high level trough water source is used, check if an overflow signal from the stabilized water tower appears. Before the formal test, it must comply with the requirements of the verification regulations. Use the verification medium to circulate in the piping system for a certain period of time. At the same time, check for leaks in the sealed pipe section;
• Before formal verification begins, the verification medium must be filled with the flowmeter sensor being tested. Then the downstream valve must be closed for zero adjustment;
• At the start of the inspection, the valve at the front of the pipe must be opened first. Gently open the valve behind the flowmeter under test to adjust the flow at the verification point; During the calibration process, the flow stability of each flow point should be within the 1% to 2%-flow method. Total legal can be within 5%. The temperature change of the test medium should not exceed 1 when the one-point flow verification process is complete. It must not exceed 5 when the whole verification process is complete;
• After each test, the valve at the front of the test pipe must be closed first, and then the pump must be stopped to avoid emptying the voltage stabilization facility. At the same time, the verification medium remaining in the test pipe should be discarded. Close control system and air compressor.

Electromagnetic flow meter price

For the price of a magnetic flowmeter, it is usually determined by the installation conditions for large pipe sizes, it is better to use the insertion type of magnetic flow meter because the price of this type of flow meter will be much cheaper when compared to the type of in-line magnetic flow meter. So are the installation costs.

However, it will affect accuracy, so if the accuracy is still a bit loose and it is allowed above 0.5% insertion magnetic flow meter is the right choice for large pipe diameter applications above 14 because the price of this type of flow meter can be considered more efficient.

Considering the price of a magnetic flow meter that is not cheap, it is better when performing the installation following the steps required by the manufacturer. There are some basic steps when installing a magnetic flow meter that might be used as a basic reference and for advanced installation steps electromagnetic flow meters

For resetting, you can look at the instructions in the installation manual, which is contained in the electromagnetic flow meter operational manual published by the manufacturer.