Advantages and disadvantages of electromagnetic flow meter

There are two ways to produce bubble-like gas in liquid, which are inhaled gas from the outside or dissolved gas in the medium is transformed into a free bubble.

The installation direction of the electromagnetic flowmeter is not particularly strict requirements, generally horizontal, vertical or inclined can be unlimited. However, it must be reminded that in order to ensure that the pipeline is full of the measured medium, that is, the “full tube” state, it is recommended to install vertically, flow from bottom to bottom, especially for liquid-solid two-phase fluids, it must be installed vertically. If the site only allows horizontal installation, it must be ensured that the two electrodes are in the same horizontal plane, and the axis of the electrode must be approximately horizontal, because the electrode at the bottom is easily covered by sediment, and the top electricity is easily wiped by the occasional bubble in the liquid, covering the electrode surface and making the output signal fluctuate. The following lists the matters that need attention in the installation of electromagnetic flowmeters:

Now, the input impedance of the electromagnetic flowmeter converter has improved a lot, and the error is basically not caused by changes in the conductivity of the medium when the conductive liquid is conductive, but for a certain converter input impedance, the conductivity of the measured medium has a lower limit min, which cannot be lower than this lower limit.

The design of electromagnetic flow meters contributes to their robustness and long-term reliability. With no moving parts in contact with the fluid, they experience less wear and tear, resulting in extended operational life and reduced maintenance requirements. This makes them particularly suitable for applications where low-maintenance and high durability are crucial factors.

electromagnetic flowmeters are employed in HVAC (heating, ventilation, and air conditioning) systems to measure the flow of water or other fluids used for temperature control. The precision and reliability of these flowmeters ensure optimal performance of HVAC systems, leading to energy savings and improved comfort in various buildings and facilities.

Medium Temperature: -20~+60 degC(Integral type)
Remote type ( Neoprene ,Hard Rubber ,Polyurethane ,EPDM) -10~+80degC
Remote type(PTFE/PFA/FEP) -10~+160degC
Ambient Temperature: -20~+60deg C
Ambient Humidity: 5-100%RH(relative humidity)
Measuring Range： Max 15m/s
Conductivity： >5us/cm
Protection Class： IP65(Standard); IP68(Optional for remote type)
Process Connection： Flange (Standard), Wafer, Thread, Tri-clamp etc (Optional)
Output Signal： 4-20mA/Pulse
Communication： RS485(Standard), HART(Optional),GPRS/GSM (Optional)
Power Supply： AC220V (can be used for AC85-250V)
DC24V (can be used for DC20-36V)
DC12V (optional), Battery Powered 3.6V (optional)

Electromagnetic flowmeter has very good characteristics, can solve other flowmeter is not easy to apply problems, such as dirty flow, corrosion flow measurement, so the application of electromagnetic flowmeter is more and more extensive. To choose a suitable electromagnetic flowmeter for yourself, you must have an understanding of it.

Due to various reasons, some large diameter flowmeters used online can not be tested off-line. It has become an urgent problem to study an online calibration method which is both scientific and effective and ADAPTS to the needs of the field. At present, there are three common methods for online calibration of electromagnetic flowmeters:

The electromagnetic flow meter consists of a non-conductive pipe lined with a conductive material, typically made of metal. The meter contains coils or electrodes positioned opposite each other on the pipe’s inner walls. A magnetic field is then generated by passing a current through these coils, creating a measurable voltage across the fluid. The induced voltage, or EMF, is directly proportional to the fluid’s velocity, allowing the flow meter to accurately determine the flow rate. Importantly, this principle remains effective regardless of the fluid’s conductivity, making electromagnetic flow meters suitable for a wide range of applications, including water, wastewater, and various industrial processes.

The reason why the measurement error is large is that the amount of oil and suspended matter in the water from the sewage station is high, and the treated sewage has a small amount of oil and suspended matter in the water, and the error of electromagnetic flowmeter measurement is also small.

The insert type electromagnetic flowmeter is an instrument used to measure conductive liquids, especially for large diameter pipe measurements.

Electromagnetic flowmeters, also known as magmeters, are devices that measure the flow of electrically conductive fluids using the principles of electromagnetic induction. There are several types of electromagnetic flowmeters, each with its own characteristics and applications. Here are some common types:

The converter direction of an electromagnetic flowmeter refers to the orientation or alignment of the flowmeter’s electronic converter unit concerning the flow direction within the pipe. Electromagnetic flowmeters typically have a preferred or specified direction for the converter to achieve optimal performance. The converter contains the electronics and signal processing components essential for accurate flow measurement.

In the electromagnetic flowmeter installation and debugging stage there will be some failures, below, we will understand the specific causes of the failure at this stage and their elimination methods.

The selection of circulating water flowmeter is a decision process involving many aspects, which needs to consider the characteristics of circulating water, measurement requirements, environmental conditions, economic costs and the performance characteristics of the flowmeter. Here is a comprehensive analysis and recommendations for the best options:

Electromagnetic flowmeter selection principle:

The grounding of the electromagnetic flowmeter is equipped with a grounding ring, and then the grounding ring is connected to the pipeline. If it’s lined, you need a third electrode to ground it.

Selection of lining materials for electromagnetic flowmeter

The sewage flowmeter has a wide range of applications and is favored by the owner, but the application performance of the sewage flowmeter has a great relationship with the installation on site. Aister makes the following requirements for the installation points of the sewage flowmeter:

What are the problems encountered when electromagnetic flowmeters are used in paper mills

According to the principle formula of the electromagnetic flowmeter, the induced signal potential is not affected by the change of conductivity and temperature, pressure, density and viscosity when the liquid conductivity is uniform. However, in the actual measurement, due to the following reasons, the electrical conductivity will also have some impact on the measurement.

Size: DN3-DN3000mm
Nominal Pressure: 0.6-1.6Mpa(2.5Mpa/4.0Mpa/6.4Mpa…Max 42Mpa)
Accuracy: +/-0.5%(Standard), 0.3% or 0.2% (Optional)
Liner: PTFE, Neoprene, Hard Rubber, EPDM, FEP, Polyurethane, PFA
Output Signal: 4-20mA/Pulse

Selecting the appropriate installation point for an electromagnetic flowmeter is crucial for accurate and reliable measurements. Here are some considerations and guidelines to help you choose the right measuring installation point:

One of the significant advantages of electromagnetic flowmeters is their high level of accuracy and reliability. With no moving parts in direct contact with the fluid, these devices experience minimal wear and tear, resulting in low maintenance requirements and increased longevity. Their versatility allows them to handle a broad spectrum of conductive liquids, from water and chemicals to slurries, making them suitable for a wide range of applications. Moreover, electromagnetic flowmeters are insensitive to changes in fluid properties, such as density, viscosity, and temperature, ensuring consistent and precise measurements across varying operating conditions.

Power Supply: AC220V (can be used for AC85-250V)
DC24V (can be used for DC20-36V)
DC12V (optional), Battery Powered 3.6V (optional)
Power Consumption: <20W Alarm: Upper Limit Alarm / Lower Limit Alarm Self-diagnosis: Empty Pipe Alarm, Exciting Alarm Explosion Proof: ATEX

What fault will occur during the debugging period of the plug-in electromagnetic flowmeter, the split electromagnetic flowmeter and the initial debugging fault, but once the fault is improved, it will generally not occur again under the same conditions.

Precision and flow rate of electromagnetic flow meter

Electromagnetic flow meter is one of the most popular flow meters. Flange type electromagnetic flow meter has been used for more than 50 years worldwide. It is widely used for all conductive liquids in every industry, such as water, acid, alkali, milk, slurry etc.

Electromagnetic flowmeters, also known as magmeters, are devices that measure the flow of electrically conductive fluids using the principles of electromagnetic induction. There are several types of electromagnetic flowmeters, each with its own characteristics and applications. Here are some common types:

Measuring medium: Conductive liquid
Diameter range: DN3mm～DN3000mm
Accuracy: ± 0.5% of the indicated value, optional ± 0.3% or ± 0.2%
Measuring range (Flow rate): 0.01m/s～15m/s

Electromagnetic flowmeter as a commonly used flow measurement instrument, the choice of its material is also an important factor. Because in the electromagnetic flowmeter, the part in contact with the medium is only the electrode and the inside of the measuring tube, it is necessary to select the correct electrode and lining material according to the characteristics of different media.

Electromagnetic flowmeter is composed of two parts: sensor and converter. It is based on Faraday’s law of electromagnetic induction work, used to measure the conductivity of more than 20μS/cm conductive liquid volume flow, electromagnetic flowmeter is a measurement of conductive medium volume flow induction instrument.