Application of Magnetic Flow Meters : Magnetic Flow meter measures the volumetric rate of flow any liquid that has adequate electrical conductivity. Most petroleum hydrocarbons have insufficient conductivity to be measured with a magnetic flow meter. It is rarely used in Petroleum Industry.
Magnetic Flow meters are widely used on slurries
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Advantages of Magnetic Flow Meter :
1.They respond only to the velocity of Fluid .Independent Density Viscosity and Static Pressure
2.High Rangebility 10:1
3.Bidirectional Flow Measurement
4.Fluid Temperature range -40 Deg C to +260 Deg C
5.Pressure Drop is negligible
6.Wide Variety of Size
Disadvantages of Magnetic Flow Measurement
1.Conductivity of the process fluid should be greater the 2 micromhos per centimeter
2.Special care is required for erosive application
3.Difficulties in on site calibration
4.High cost
5.Large Sizes are very heavy
Installation Consideration :
Magnetic Flow Meter consist of two parts
Primary elements installed directly in the processline
Secondary elements is an electronic transmitter
Magnetic flow meter tube may be installed in any position but it must run full of liquid for accurate measurement
I have a electromagnetic flow meter which gives 4 to 20mA. I want to use this to control a pump speed.would u like to help me how can i write a program in LAD language
Magnetic flow meters (magmeters) measure conductive liquids using Faraday’s Law of Electromagnetic Induction. They are widely used in industries where traditional flow meters struggle.
Applications of Magnetic Flow Meters
Water & Wastewater Treatment (clean water, sewage, slurries)
Chemical & Pharmaceutical Industries (acids, caustics, solvents)
Food & Beverage (milk, juice, beer, syrups)
Pulp & Paper Industry (black liquor, slurry flows)
Mining & Mineral Processing (abrasive slurries)
HVAC & Cooling Systems (chilled water, brine solutions)
Not Suitable For:
Non-conductive fluids (oils, hydrocarbons, distilled water)
Gases or steam
Low-conductivity liquids (<5 µS/cm)
Advantages of Magnetic Flow Meters
- No Moving Parts → Low Maintenance
No obstructions in the flow path, reducing wear and clogging.
- Highly Accurate (±0.5% of Rate)
Unaffected by temperature, pressure, or viscosity changes.
- Bidirectional Flow Measurement
Can measure forward and reverse flow.
- Works with Corrosive & Abrasive Fluids
Lining options (rubber, PTFE, PFA) protect against harsh chemicals.
- Minimal Pressure Drop
Smooth flow path unlike orifice plates or vortex meters.
- Wide Turndown Ratio (Up to 100:1)
Effective across a broad flow range.
- Handles Dirty & Slurry Liquids
Ideal for wastewater, mining slurries, and pulp processing.
Disadvantages of Magnetic Flow Meters
- Requires Conductive Liquid (≥5 µS/cm)
Cannot measure hydrocarbons, oils, or pure water.
- High Initial Cost
More expensive than mechanical meters but cheaper than Coriolis.
- Needs Full Pipe for Accuracy
Air bubbles or partial filling can cause errors.
- Affected by Electrical Noise
Proper grounding is critical to avoid signal interference.
- Limited for High-Temperature Applications
Some linings (e.g., PTFE) have temperature limits (~180°C).