Electromagnetic Water Flow Meter
Municipal & Industrial Water Build
Accuracy of ±0.5% of rate
Conductivity threshold ≥ 5 µS/cm
Velocity range 0.3 to 15 m/s
- Line sizes DN10 to DN3000
- Hard rubber liner standard, PTFE option for chemical water
- 316L stainless electrode, IP68 submersible option
The Electromagnetic Water Flow Meter is the standard LEA build for municipal supply, distribution mains, HVAC chilled water, and industrial process water—Faraday’s law, full-bore, zero pressure loss.
Hard rubber liner + 316L electrode covers DN10–DN3000 at PN10–PN40; PTFE liner for chemical-water carry-over. IP68 sensor + IP65 converter for buried/flooded chambers; CNEX Ex d optional. Lead time 5–7 business days.
Benefits
- ±0.5 % of rate standard; ±0.2 % high-accuracy version for revenue-grade water.
- 5D/2D straight-pipe footprint—half the vortex rule, quarter the orifice rule.
- Full-bore zero pressure loss: no bluff body; ideal for distribution mains and chilled-water loops.
- Bi-directional with separate forward/reverse totalizers for district-heating return-line service.
- IP68 sensor + IP65 converter for buried valve chambers and flooded lift stations.
- DN10–DN3000 covers branch sub-meters through trunk mains on one code system. Lead time 5–7 days.
Typical applications
Four water-service zones where electromagnetic measurement is the standard choice over vortex, ultrasonic, or mechanical alternatives.
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Municipal supply & distribution
City mains, DMAs, pump-station discharge; IP68 fits valve chambers.
Hard rubber · DN50–DN1500❄️
HVAC chilled water & district energy
Branch sub-measurement for tenant billing; bi-directional totalizer handles return-line.
Hard rubber · DN25–DN300🏭
Industrial process water
Plant utility, cooling-tower make-up, boiler-feedwater intake, recycle loops above 5 µS/cm.
Hard rubber/PTFE · DN50–DN600💧
Irrigation & agricultural water
Centre-pivot, well-pump discharge, farm mains; battery + 4G IoT for off-grid.
Hard rubber · DN50–DN500Flow range by pipe size.
Volumetric flow at water reference (1000 kg/m³) across the 0.3 to 15 m/s velocity range. Full DN6 to DN3000 range available; the table below shows the most common water-service sizes.
| DN | Inches | @ 1 m/s (m³/h) | @ 3 m/s | @ 5 m/s | @ 15 m/s (max) |
|---|---|---|---|---|---|
| DN15 | 1/2″ | 0.64 | 1.91 | 3.18 | 9.54 |
| DN25 | 1″ | 1.77 | 5.30 | 8.84 | 26.51 |
| DN50 | 2″ | 7.07 | 21.21 | 35.34 | 106.03 |
| DN80 | 3″ | 18.10 | 54.29 | 90.48 | 271.43 |
| DN100 | 4″ | 28.27 | 84.82 | 141.37 | 424.12 |
| DN150 | 6″ | 63.62 | 190.85 | 318.09 | 954.26 |
| DN200 | 8″ | 113.10 | 339.29 | 565.49 | 1696.46 |
| DN300 | 12″ | 254.47 | 763.41 | 1272.35 | 3817.04 |
| DN500 | 20″ | 706.86 | 2120.58 | 3534.29 | 10602.88 |
| DN800 | 32″ | 1809.56 | 5428.67 | 9047.79 | 27143.36 |
| DN1000 | 40″ | 2827.43 | 8482.30 | 14137.17 | 42411.50 |
| DN1500 | 60″ | 6361.73 | 19085.18 | 31808.63 | 95425.88 |
| DN2000 | 80″ | 11309.73 | 33929.20 | 56548.67 | 169646.00 |
Specifications
| Measurement principle | Faraday’s law of electromagnetic induction |
|---|---|
| Pipe size range | DN10 – DN3000 (3/8″ – 120″) |
| Accuracy | ±0.5 % of rate standard, ±0.2 % of rate high-accuracy option, ±2.5 % of rate verification grade |
| Velocity range | 0.3 to 15 m/s (1:1500 turndown maximum, typical operation 1–5 m/s) |
| Conductivity threshold | ≥ 5 µS/cm |
| Working pressure | PN10 / PN16 / PN25 / PN40 standard (ANSI 150 to 600 LB), up to PN250 (25 MPa) on request |
| Medium temperature | 0 to +80 °C standard water service (extended range available with PTFE liner) |
| Ambient temperature | −40 to +60 °C |
| Liner material | Hard rubber (D) standard, PTFE (F4 / C) for chemical water, soft rubber (E) for sewage carry-over |
| Electrode material | 316L stainless standard, Hastelloy C optional for chloride service |
| Connection | Flanged (PN / ANSI) standard, sandwich (wafer) optional |
| Output signals | 4-20 mA + HART, RS485 Modbus RTU, pulse, alarm contact, 4G IoT |
| Power supply | 24 V DC, 220 V AC, or battery (lithium, 5-year service life typical) |
| Ingress protection | IP65 standard, IP67 sensor + IP65 converter, IP68 sensor + IP65 converter (submersible option) |
| Hazardous area | Ex d optional for petrochemical-plant process-water service |
| Approvals | EMC 2014/30/EU (Annex II), CE, ISO 9001 calibration certificate with each meter |
Installation
Five install requirements. Liner material and ingress rating lock at the factory; the mount orientation, bypass plumbing, grounding discipline, and cable routing below are the on-site rules that matter.
- Mount vertical with upward flow, or horizontal with electrodes at 3 and 9 o’clock Vertical mounting with bottom-to-top flow guarantees full-bore wetting and is the factory preferred orientation. If horizontal mounting is the only site option, the two electrodes must sit on the same horizontal plane (3 and 9 o’clock positions of the bore cross-section, not 12 and 6).
- Install valves and bypass at both ends of the sensor Per installation requirements, valves on both sensor ends plus a bypass loop allow sensor isolation for inspection, cleaning, or replacement without shutting down the process; particularly important on continuous water-distribution mains.
- Ground sensor housing, both pipe ends, and converter to ≤10 Ω The few-millivolt EMF measured by the electrodes references internal sensor potential. Ground the sensor housing, both ends of the metal pipe, and the converter housing to a grounding line that is not shared with other electrical equipment. Resistance must be ≤10 Ω. On plastic-lined or non-metallic pipe sections, connect the sensor housing to the metal pipe with a metal grounding wire first.
- Use shielded signal cable ≤30 m, never parallel with power in the same conduit Sensor-to-converter signal must use the supplied shielded cable. Maximum length 30 m standard. Signal and power cables must NOT run parallel inside the same cable steel conduit. Grounding the shield at the converter end only (not both ends) prevents ground-loop interference on the µV-level induced EMF.
- Do NOT install on the pump suction side; place the regulating valve downstream Vacuum-induced negative pressure on the pump suction side breaks the EMF measurement. Always install on the pump discharge side. Place flow regulating valves downstream of the sensor; never upstream; so flow profile asymmetry from valve throttling does not affect the cross-sectional average.
Frequently asked questions
What is an electromagnetic water flow meter and how does it work?+
An electromagnetic water flow meter measures volumetric flow of water by Faraday’s law of electromagnetic induction. A pair of magnetic-field coils generates a stable field across the pipe bore. As water (with conductivity above 5 µS/cm) flows through the field, an electromotive force is induced across two electrodes in the pipe wall, with magnitude directly proportional to the average flow velocity. The meter delivers ±0.5 % of rate typical accuracy with a 0.3 m/s low-flow detection.
What pipe sizes and pressure classes are available for water service?+
The meter covers DN10 to DN3000 (3/8″ to 120″) pipe sizes. Standard pressure classes are PN10, PN16, PN25, and PN40 (ANSI 150 to 600 LB); covering municipal distribution, industrial process water, and most HVAC applications. Higher pressure classes up to PN250 (25 MPa) are available on special order. Hard rubber liner is standard for general water; PTFE liner is available for chemical-process water.
What straight-pipe footprint does the electromagnetic water meter need?+
The meter measures the average velocity across the full pipe cross-section directly through the induced EMF. Velocity profile asymmetry from elbows, valves, or reducers does not significantly change the cross-sectional average, so the straight-pipe rule is short: 5D upstream and 2D downstream. This is the key advantage on retrofit installations where pipe length is constrained; the meter drops into existing skids and pipe runs that vortex (10D / 5D) and orifice (20D / 5D) meters cannot fit.
What is the conductivity floor and what waters fall below it?+
The meter requires water conductivity above 5 µS/cm. Tap water (50–500 µS/cm), well water, river water, sea water (50,000 µS/cm), and any process water with dissolved salts are well above the threshold. Below threshold: deionized water (DI), demineralized boiler-feedwater after polishing (often below 1 µS/cm), and condensate from clean steam. For DI water and clean condensate, choose vortex (LUGB) liquid build, Coriolis, or thermal-mass meters that do not rely on conductivity.
Can the meter be installed underground or in flooded chambers?+
Yes; the IP68 sensor + IP65 converter combination is the standard option for buried installations, valve chambers, and lift stations subject to flooding. The sensor head with hermetic potting handles continuous submerged service; the remote-mount converter housing stays at IP65 above grade for technician access. The 24 V DC option supports battery backup or solar power on remote distribution sites.
What output options are available for SCADA and metering integration?+
The meter outputs 4-20 mA + HART for analogue loop integration, RS485 Modbus RTU for serial polling, pulse output for totalizer counting, alarm contacts for high / low limits, and 4G IoT for remote sub-measurement without on-site SCADA. The integral display shows instantaneous flow rate, totalized volume (forward + reverse), velocity, and unit-conversion options. Battery-powered versions extend telemetry to off-grid distribution mains.
What is the lead time and what certification ships standard?+
Standard lead time is 5–7 business days from order confirmation, factory direct. EMC compliance to the EU Electromagnetic Compatibility Directive 2014/30/EU (Annex II) ships standard. IP65, IP67, and IP68 sensor + IP65 converter ingress ratings are selectable. Ex d hazardous-area certification is available for petrochemical-plant process-water service.
Need help sizing the water build?
Send line size, pipe material, pressure, water source, and design flow—sized model code and ship window within one business day.