When talking about measuring the sewage flow rate, we prefer the electromagnetic flowmeter. The working principle of the electromagnetic flowmeter is Faraday’s Law of induction. When the measured liquid passes the flow sensor tube with more than 5μS/cm conductivity, a magnetic field produced by the coils which results in the induction of voltage.
Magnetic flowmeters have many advantages in measuring wastewater:
1. Magnetic flowmeters have no moving parts and are therefore extremely durable.
2. Sewage/waste water is complicated and even has particles. Therefore, turbine flowmeters, vortex flowmeters, and oval gear flow meters are not suitable. Coriolis mass flowmeters are very expensive and are not suitable for measuring sewage flow rate.
3. If industrial wastewater is corrosive, we can choose PTFE lining and anti-corrosion electrodes to measure the sewage flow.
4. The technology of mag meter has been very stable, and electromagnetic flowmeters which made in China now are in cheap price but also stable in operation.
5. Mag meter can be powered by battery, and can even provide GPRS communication, which solves the problem of no power supply in the remote area.
6. Electromagnetic flowmeters are available in a variety of sizes, such as 2 inch, 4 inch, 6 inch, and we even offer a maximum 2200mm sewage flow meter. For pipes over 6 inches, we can choose a plug-in electromagnetic flowmeter to save cost.
7. Electromagnetic flowmeters have digital display to show total flow and instant flow,it can also have various communications, such as 4-20mA, pulse, RS485 and so on.
8. The accuracy of the magnetic flowmeter reaches 0.5%. The accuracy is relatively high. We even provide a magmeter with an accuracy of 0.25-0.3%.
In short, the electromagnetic flowmeter is kind of a very economical sewage /waste water flowmeter.
If we want to choose correct type sewage flow meters, we should prepare below specifications:
1. Provide pipe size and flow range to flow meter supplier to determine the sewage flow meter size.
2. Provide operation temperature and pressure to check whether it is in high temperature or high pressure condition.
3. Tell flow meter factory whether it has solids or the waste water is corrosive, if it has particles inside , we could choose rubber liner which is more abrasive, if it is corrosive , we could choose PFA or PTFE liners.
4. Tell the mag meter factory power supply, also special function you need, such as you need Hart protocol or you need RS485.
5. Tell the flow meter supplier process connection, whether you need ANSI flange or DIN flanges, whether you need grounding rings or not.
Click below for more technical specifications for Electromagnetic flow meter also email us to obtain the low cost sewage flow meter.