Ultrasonic Flow Sensors
Reliable, Accurate Flow Measurement
Reliable measurement of flow plays an essential role in maximizing HVAC system efficiency, conserving energy, and ensuring occupant comfort. Flow sensor utilizing ultrasonic transit-time technology provides accurate and repeatable flow measurements of water and water/glycol mixtures without drift in any HVAC application.
The innovative measurement method features:
Multi-point wet calibrated to ensure accuracy and repeatability.
Patented temperature and glycol compensation logic eliminates manual calibration.
±2% accuracy of reading and ±0.5% repeatability ensure accurate and precise flow measurement.
Ultra-compact size with a short inlet length of 5 x nominal pipe diameter and no output-length requirements allow the ultrasonic flow sensor to be installed in tight spaces.
Low power consumption of 0.5W saves energy and transformer capacity.
Belimo FM series flow sensors with ultrasonic technology and glycol and temperature compensation to accurately measure water flow for HVAC plant applications and sub-metering of hot or chilled water flow. The compact size and rugged design make the ultrasonic flow sensor suitable for use with chilled water, hot water, and water/glycol solutions at temperatures ranging from -4...250°F [-20...120°C].
Why is Glycol Compensation Important?
The addition of glycol is the most common way to protect water-based HVAC systems exposed to freezing temperatures. Adding glycol lowers the freezing point which increases the boiling point and has a significant influence on the viscosity, density, and heat capacity of the HVAC systems.
Determining the flow/thermal energy without taking the water temperature and glycol concentration into account could lead to measuring errors. Insufficient or unreliable water temperature readings could distort the heat coefficient by up to 18%. Inaccurate or unknown glycol water compositions may lead to deviations of up to 30% of the volumetric flow.
Unlock Powerful Insights on Overcoming Glycol Measurement
Join us for a webinar on September 10th
How to Protect Your System and Save Money by Understanding the Effects of Glycol on HVAC Systems
Every year too much energy is wasted because of inefficient HVAC glycol concentration. It is critical to measure glycol concentration to ensure freeze protection and even more to optimize HVAC/cooling system efficiency. If your glycol content is too low or high, your pipes may burst, thus wasting money on unnecessary pump power.
You will learn
- Fundamentals of heat transfer
- How glycol is used in HVAC systems
- Measuring heat transfer (with water)
- The influence of glycol on the measurement of heat
- How important it is to constantly monitor the glycol concentration
- Alternative ways to measure heat transfer
Ultrasonic Flow Sensors Features
- Multi-point wet calibrated to ensure accuracy and repeatability.
- Patented temperature and glycol compensation logic eliminates manual calibration.
- ±2% accuracy of reading and ±0.5% repeatability ensure accurate and precise flow measurement.
- Ultra-compact size with a short inlet length of 5 x nominal pipe diameter with no output-length requirements allows installation in tight spaces.
- Low power consumption of 0.5 W saves energy and transformer capacity
Accurate Results Without Drift
The development of an inline flow sensor that uses ultrasonic transit-time technology to automatically measure and compensate for glycol concentration is a huge advance in thermal energy measurement. A single ‘fit and forget’ flow sensor is all that is necessary to compensate for the variable and changing viscosities and heat capacities of heat transfer fluids comprising up to 60 percent glycol. With no moving parts, the sensor is extremely robust and requires no calibration, providing certainty that the measured flow is correct. This makes it ideal for accurate, repeatable measurements, improving the control and efficiency of HVAC systems.
Ease of Installation and Commissioning
The ultrasonic flow sensor compact size ensures easy installation even in tight spaces. The comprehensive diagnostics functions feature an automatic air-bubble and water presence detection. The multi-point wet calibration enables hassle-free installation and accurate flow measurement from start-up. Their compact size and rugged design make the ultrasonic flow sensor suitable for use with chilled water, hot water, and water/glycol solutions at temperatures ranging from -4...250°F [-20...120°C].