Which Liquid Cannot Be Measured By The Magnetic Flowmeter?

Many industrial users waste money on magnetic flowmeters only to discover they won’t work with their non-conductive liquids like oils or pure water.

Magnetic flowmeters cannot measure non-conductive liquids such as oils, hydrocarbons, ultra-pure water, and most organic chemicals due to their requirement for fluid conductivity above 5µS/cm.

Non-conductive Liquids and Magnetic Flowmeters

Let me share my experience with magnetic flowmeter applications and limitations.

Which Liquid Cannot Be Measured By The Magnetic Flow Meter?

I often see customers struggling with magnetic flowmeter failures when trying to measure the wrong types of liquids.

Non-conductive liquids that magnetic flowmeters cannot measure include petroleum products, pure water, alcohols, and most hydrocarbon-based chemicals.

Based on my field experience:

Non-Measurable Liquids

1. Common Examples

   Liquid Type	Conductivity	Why It Won’t Work	Alternative Solution
   Petroleum	<1µS/cm	Too low conductivity	Turbine meter
   Pure water	<1µS/cm	Insufficient ions	Ultrasonic meter
   Alcohol	<2µS/cm	Non-polar molecule	Coriolis meter
   Oils	<1µS/cm	Non-conductive	PD meter

2. Key Characteristics¹

   • Molecular structure
   • Ion content
   • Chemical composition
   • Electrical properties

Technical Limitations

1. Operating Principles

   • Faraday’s law requirements²
   • Conductivity thresholds
   • Signal generation
   • Measurement accuracy

2. Application Constraints

   • Minimum conductivity needs
   • Temperature effects
   • Installation requirements
   • Maintenance considerations

What Type Of Fluids Can Magnetic Flow Meters Measure?

Many operators are unsure about which fluids will work well with magnetic flowmeters.

Magnetic flowmeters can measure conductive fluids including water, wastewater, chemicals, pulp, slurries, and any liquid with conductivity above 5µS/cm.

Fluids Suitable for Magnetic Flowmeters

From my implementation experience:

Suitable Fluids

1. Common Applications

   Fluid Type	Typical Conductivity	Best Applications	Key Benefits
   Water	>50µS/cm	Distribution	No pressure loss
   Wastewater	>100µS/cm	Treatment plants	Handles solids
   Chemicals	>20µS/cm	Process control	Chemical resistant
   Slurries	>50µS/cm	Mining	Abrasion resistant

2. Performance Factors

   • Conductivity levels
   • Solid content
   • Flow velocity
   • Temperature range

Implementation Guidelines

1. Selection Criteria

   • Process requirements
   • Fluid properties
   • Installation conditions
   • Maintenance needs

2. Operational Considerations

   • Grounding requirements
   • Liner selection
   • Electrode materials
   • Signal processing

What Type Flow Meter Is Not Applicable For Non-Conductive Liquids?

Understanding which flowmeters won’t work with non-conductive liquids can save time and money in project planning.

Magnetic flowmeters are not applicable for non-conductive liquids as they rely on Faraday’s law of electromagnetic induction, requiring electrical conductivity in the fluid.

Alternative Solutions for Non-conductive Liquids

Drawing from my expertise:

Alternative Solutions

1. Technology Options

   Meter Type	Working Principle	Advantages	Applications
   Ultrasonic	Sound waves	Non-invasive	Clean liquids
   Coriolis	Mass flow	High accuracy	All liquids
   Turbine	Mechanical	Cost-effective	Low viscosity
   PD	Volume displacement	High accuracy	High viscosity

2. Selection Guidelines

   • Fluid properties
   • Process conditions
   • Accuracy needs
   • Budget constraints

Application Considerations

1. Implementation Factors

   • Installation requirements
   • Maintenance access
   • Environmental conditions
   • Performance monitoring

2. Operational Requirements

   • Calibration needs
   • Cleaning procedures
   • Spare parts
   • Technical support

Do Magnetic Flow Meters Measure Viscosity?

Plant operators often ask about additional measurement capabilities of magnetic flowmeters.

No, magnetic flowmeters cannot measure viscosity as they only measure volumetric flow rate based on electromagnetic induction principles.

Based on my experience:

Measurement Capabilities

1. Parameter Overview

   Parameter	Can Mag Meter Measure?	Alternative Solution	Application
   Flow rate	Yes	Primary function	All conductives
   Viscosity	No	Coriolis meter	Process control
   Density	No	Nuclear/Coriolis	Quality control
   Temperature	Indirect	RTD/Thermowell	Process monitoring

2. Technology Limitations

   • Single parameter measurement
   • Conductivity dependence
   • Operating principles
   • Signal processing

Additional Considerations

1. Multi-Parameter Needs

   • Process requirements
   • Instrument selection
   • Integration options
   • Cost implications

2. Solution Development

   • Application analysis
   • Technology matching
   • Implementation planning
   • Performance validation

Conclusion

Magnetic flowmeters are excellent for conductive fluids but completely unsuitable for non-conductive liquids, requiring careful consideration of fluid properties and alternative technologies for successful flow measurement.