Electromagnetic water meters and electromagnetic flowmeters consist of a sensor and a converter. They both use the principle of electromagnetic induction, but this does not mean that the two products are the same.
An electromagnetic water meter is also a kind of electromagnetic flowmeter. As electromagnetic flowmeters measure a variety of media, there is a wide range of electromagnetic flowmeters on the market. Electromagnetic flow meters have requirements of the press they measure. Not only should it be electrically conductive, but it should also have a specific dielectric constant.
Electromagnetic water meters and electromagnetic flowmeter is still different. The difference between them is mainly reflected in the following aspects.
1. Application areas
The electromagnetic water meter is mainly used in the municipal sector. It is mainly used to measure clear water and raw water. It can also solve the water source and urban and rural water supply measurement, statistics, analysis, settlement function.
An electromagnetic flowmeter can measure a variety of conductive media. It is suitable for continuous measurement of flow in industrial production. It also has achievements in production control, measurement, and control of scientific research.
2. Accuracy
Electromagnetic water meter: its accuracy is usually ±2% (Q2~Q4±2%, Q1~Q2±5%), high precision can reach â… (Q2~Q4±1% Q1~Q2±3%)
Electromagnetic flowmeter: its accuracy is usually ±5%, high precision up to ±0.2%, ±0.3%.
3. Size
Electromagnetic water meter: it is mainly DN50 ~ DN300 diameter, the whole series of DN25 ~ DN800 diameter
Electromagnetic flowmeter: It is primarily DN25 ~ ND600 diameter, the whole series of DN10 ~ DN3000 diameter.
4. Range range (metering flow rate range) and range migration
Electromagnetic water meter of high measurement flow rate up to 15m / s. Electromagnetic water meter flow point Q3 selected in 12.5 ~ 13.5m / s flow rate. Electromagnetic water meter does not have the concept of “range migration.” Its measurement range in the initial flow QS to the large flow Q4 between. When choosing the diameter of the electromagnetic water meter, we should mainly consider meeting the economic flow rate.
Electromagnetic flowmeter medium flow rate measurement range is usually 0.4 ~ 12m / s. Electromagnetic flowmeter measurement upper flow point can “migrate” flow rate range of 1 ~ 10m / s. We choose the electromagnetic flowmeter diameter. We should consider the economic flow rate of 2.5 ~ 4.5m3 / h, and we should also consider its process requirements.
5. Power supply method
An internal power supply battery mainly powers the electromagnetic water meter.
The electromagnetic flowmeter is mainly powered by mains electricity (AC220V) and a unique external power supply (DC24V).
6. Repeatability
Electromagnetic water meter: we do not take the repeatability to assess quality indicators. It is only a design and experimental hand.
Electromagnetic flowmeter: its repeatability index is usually 1/3 of the accuracy.
7. Sampling rate
Electromagnetic water meter: its sampling rate in the range of 1 to 30 s / times (the lower the sampling rate, the lower the power consumption)
Electromagnetic flowmeter: its sampling rate is generally required to be higher than 100 ms/time
8. Communication methods
The electromagnetic water meter comes with IR, RS-485, and IoT communication. It has manual meter reading and switches output.
The electromagnetic flowmeter has quantitative pulse output, output current (4~20mA), and frequency output. It can also come with RS-485 communication and switching output.
9. Using environment
9.1 Temperature
Electromagnetic water meter generally in the 0. 1 ~ 55 ℃ temperature environment in continuous operation.
Electromagnetic flowmeter is usually in the – 20 ~ 55 ℃ temperature environment. Therefore, it can work continuously is stable and reliable.
9.2 Protection
With the technology and environmental improvements, the protection standard is also gradually improved. For example, the electromagnetic water meter implements the IP68 standard. It is required in the 2 m water depth of the environment for more than ten days.
The use of electromagnetic flowmeters is prevalent. However, its operating environment is complex. Therefore, manufacturers have designed different protection methods for users to choose from for different user environments.
If we use the IP66 standard general-purpose electromagnetic flowmeter, it can only protect against rainfall. So instead, we should use a unique sealed high-temperature resistant design in high temperature and high humidity environments.
Using a submersible electromagnetic flowmeter, we have to design the protective housing according to the IP68 standard because of some dangerous occasions (textile mills, flour processing plants, chemical plants, coal mines, flammable and explosive places). Therefore, we must design the housing protection according to the explosion-proof standard when using the electromagnetic flowmeter. Thus, electromagnetic flowmeter manufacturers will usually be by the user’s environmental conditions to provide the appropriate product protection.
9.3 Maintenance
Electromagnetic water meters have a long testing cycle (around two years). Usually, almost in a state of no supervision, large-diameter meter data values significantly impact the measurement and settlement, thus requiring higher quality in their design, testing, and manufacturing.
10. Conclusion
Electromagnetic flowmeter is widely used in chemical, petroleum, metallurgy, electric power, food, medicine, textile, and other fields. It can measure the liquid of the conductive medium. An electromagnetic water meter is used for water trade measurement in the water industry, which can complete the reasonable distribution, dispatching, size, and settlement of water more stably and accurately.
In summary, electromagnetic water and flowmeters are two completely different products. The measurement principle is the only common point. For electromagnetic water meters, it is more technically difficult.