Micronics U3300-HM Clamp On Ultrasonic BTU Flow Meter

The U3300 HM is a clamp on ultrasonic heat and energy meter for permanent installation on closed hydronic systems. It combines transit time ultrasonic flow measurement with paired PT100 temperature sensors mounted on the supply and return lines. The unit calculates thermal energy by comparing flow rate with the measured temperature difference and applies standard values for water and water glycol mixtures. Nothing enters the pipe so installation does not require cutting, draining or shutting down equipment.

Setup is handled through the wall mounted display and keypad. The installer enters pipe size, material and fluid type, and the instrument calculates the correct transducer spacing. The PT100 sensors are clamped directly onto the pipe surface to measure supply and return temperatures. Once running, the meter displays flow, delta T, energy rate and totalized energy while providing electrical outputs for integration with building or plant energy management systems.

Permanent ultrasonic heat meter for continuous thermal energy monitoring in closed loop systems.
The U3300HM delivers continuous thermal energy measurement using clamp on ultrasonic flow sensing and dual temperature inputs, supporting long term monitoring in industrial and building systems.

Download technical documentation, manuals, and product literature for reference.

Product Features

  • Clamp on flow and temperature sensing for non intrusive installation
  • Transit time ultrasonic flow measurement with cross correlation processing
  • Paired PT100 Class B temperature sensors for delta T measurement
  • Energy rate and total energy display for heating and cooling circuits
  • Flow rate, flow velocity and total flow measurement
  • Quickstart style setup with multi language support
  • Continuous display of signal strength and system status values
  • Wall mounted IP65 enclosure with integrated display and keypad
  • Suitable for full pipe systems with clear fluids under three percent solids
  • Works on steel stainless steel copper and plastic pipes
  • Optional IP68 transducers and high temperature transducer sets

Technical Specs

  • Transit time ultrasonic flow measurement
  • Velocity range roughly 0 to 20 meters per second equivalent
  • Accuracy typically one to three percent depending on installation
  • A transducers for 0.51 to 4.5 inch pipe OD
  • B transducers for 2 to 79 inch pipe OD
  • PT100 Class B sensors for supply and return temperatures
  • Temperature range up to 392 degrees Fahrenheit with high temp sensors
  • Minimum delta T around 0.3 degrees Celsius equivalent
  • IP65 wall mounted electronics enclosure
  • Power input 86 to 264 volt AC or optional 24 volt module
  • One isolated milliamp output for flow or power
  • Three pulse outputs for volume energy or alarms
  • USB export to CSV for logged data
  • Data logging capacity up to one hundred million points

Applications

  • HVAC heating and cooling loops
  • Chilled water and hot water energy metering
  • Condensate return line monitoring
  • District energy systems
  • Building energy monitoring and audits
  • Commercial and industrial hydronic systems
  • Process water and utility water circuits
  • Boiler and chiller performance analysis
  • Heat exchanger efficiency tracking
  • Sanitary and wash down environments
  • Clean in place process verification
  • High temperature fluid measurement with suitable sensors
  • Data logging for flow and energy evaluation
  • Permanent non intrusive flow and energy monitoring
  • Systems with bidirectional flow conditions
  • Installations requiring long sensor cable runs

Industries

  • Commercial HVAC and building energy management
  • Institutional and campus heating and cooling systems
  • Industrial process heating and cooling
  • Water treatment and utility distribution
  • Pharmaceutical and biotech hydronic systems
  • Food and beverage plant utility water circuits

Optional Product Accessories or Add-ons

  • Data logger with USB export
  • Modbus RTU communication
  • 24 volt AC or DC power module
  • High temperature transducers
  • IP68 rated transducers
  • Extended length transducer cables

Still not sure which one you need?

You can use our short questionnaire to narrow down the best clamp on flow meter for your application. It asks a few simple questions and points you in the right direction. If you prefer to talk with a live person, please give us a call!
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