| Electromagnetic Flow Meter | Volumetric flow rate | Faraday's law of electromagnetic induction | Conductive liquids, wastewater, slurries, chemicals | Water treatment Food processing Chemical dosing Mining | Approximately ±0.2% to ±1.0% of reading | Requires electrically conductive liquid; no moving parts; straight-pipe requirements and lining compatibility should be checked. |
| Ultrasonic Flow Meter | Liquid or gas flow rate | Transit-time or Doppler measurement using ultrasonic signals | Water, hydrocarbons, gases, wastewater and clean liquids | Pipeline monitoring District energy Water networks Temporary measurement | Approximately ±0.5% to ±2.0% of reading | Clamp-on versions support retrofit installation; performance depends on pipe condition, acoustic coupling, flow profile and fluid characteristics. |
| Coriolis Mass Flow Meter | Mass flow, density and often temperature | Coriolis force generated by vibrating flow tubes | Liquids, gases, slurries and high-value process fluids | Batching Custody transfer Fuel loading Pharmaceutical production | Approximately ±0.1% to ±0.5% of reading for liquids | Provides direct mass measurement and high repeatability; pressure drop, line size, vibration and two-phase flow must be evaluated. |
| Positive Displacement Flow Meter | Volumetric flow rate | Counts fixed volumes trapped and displaced by internal elements | Oils, fuels, lubricants, solvents and other clean liquids | Fuel dispensing Lubricant transfer Oil terminals Chemical batching | Approximately ±0.1% to ±0.5% of reading | Strong low-flow performance and repeatability; fluid cleanliness, viscosity, pulsation and moving-part wear are important. |
| Turbine Flow Meter | Volumetric flow rate | Rotor speed proportional to fluid velocity | Clean, low-viscosity liquids and gases | Fuel measurement Compressed gases Process utilities Laboratory systems | Approximately ±0.5% to ±1.0% of reading | Requires a developed flow profile; bearings and rotor components can be affected by particulates, viscosity changes and excessive flow velocity. |
| Variable Area Flow Meter | Instantaneous flow rate | Float position changes inside a tapered tube | Low-to-medium flow liquids and gases | Purge systems Laboratory use Gas panels Cooling circuits | Approximately ±1.5% to ±5.0% of full scale | Simple and economical; readings depend on fluid density, viscosity, pressure, temperature and installation orientation. |
| Differential Pressure Flow Meter | Flow rate, pressure and pressure loss | Calculates flow from pressure difference across a primary element | Liquids, gases and steam | Steam systems Refineries Process plants Utility monitoring | Approximately ±1.0% to ±2.5% of reading | Applicable to many process conditions; permanent pressure loss, impulse-line maintenance and square-root extraction should be considered. |
| Thermal Mass Flow Meter | Mass flow of gas | Measures heat transfer from a heated sensor to the flowing gas | Air, nitrogen, oxygen, natural gas and other clean gases | Compressed-air audits Gas distribution Combustion control Environmental monitoring | Approximately ±1.0% to ±2.0% of reading | Provides direct mass-flow indication without pressure or temperature compensation in many designs; gas composition and contamination affect performance. |
| Vortex Flow Meter | Flow rate of liquids, gases or steam | Measures vortex shedding frequency behind a bluff body | Water, steam, compressed air and process gases | Steam metering Boiler systems Utility allocation Process monitoring | Approximately ±0.7% to ±2.0% of reading | No moving parts; adequate velocity, vibration control, straight-run piping and proper compensation for temperature or pressure are required. |
| Radar Level Meter | Liquid or solid level | Time-of-flight measurement using microwave signals | Water, chemicals, oils, powders, grains and bulk solids | Storage tanks Silos Chemical processing Inventory control | Typically about ±3 to ±10 mm, depending on design and conditions | Non-contact measurement; antenna selection, surface turbulence, foam, condensation, obstructions and dielectric properties influence results. |
| Hydrostatic Level Transmitter | Liquid level or hydrostatic pressure | Measures pressure generated by the liquid column | Water, wastewater and compatible process liquids | Open tanks Reservoirs Lift stations Irrigation systems | Approximately ±0.1% to ±0.25% of calibrated span | Cost-effective for tanks and wells; liquid density, venting, submergence, sediment and diaphragm protection must be considered. |
| Pressure Transmitter | Gauge, absolute or differential pressure | Converts diaphragm deformation into an electrical signal | Liquids, gases, steam and process fluids | Pipeline control Pump monitoring Hydraulics Process automation | Approximately ±0.05% to ±0.25% of span | Range, overpressure protection, wetted-material compatibility, temperature effects and impulse-line configuration are key factors. |
| Industrial Temperature Meter | Temperature | Resistance change in RTDs or voltage generation in thermocouples | Liquids, gases, solids and process equipment | Furnaces Food processing HVAC Chemical plants | RTD systems commonly ±0.1°C to ±0.3°C; thermocouple systems commonly ±1°C to ±2.5°C | Sensor type, thermowell response time, insertion depth, calibration class and electrical noise affect measurement quality. |
| Energy or Heat Meter | Thermal energy, flow, supply temperature and return temperature | Calculates energy from measured flow and temperature difference | Water or water-glycol heating and cooling circuits | District heating Chilled-water systems Commercial buildings Industrial utilities | Typically about ±1.5% to ±5.0% of measured energy, depending on the complete system | Flow sensor, temperature sensors and calculator must be matched; low temperature difference and installation conditions can significantly affect accuracy. |