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High sensitivity at low flows detects pressure drops in medical applications
Honeywell Published: 02/29/2012
(Honeywell: Minneapolis) -- Honeywell has added new flow ranges to its Zephyr Analog and Digital Airflow Sensor portfolio to provide high sensitivity at very low flows, making the sensor portfolio ideal for use in a variety of medical equipment and industrial applications.
Four standard flow ranges between ±50 standard cubic centimeters per minute (SCCM) and ±750 SCCM have been added to the existing flow range of ±200 SCCM. In addition, a new port/housing style, the short port fastener mount, has also been added to the portfolio. The extended flow ranges give the Zephyr the ability to detect low-pressure drops that often occur in medical applications that can affect patient comfort. The ranges also reduce noise and system wear on components, such as motors and pumps. In industrial applications, lower flow-range detection can optimize performance in gas leak detection and clogged heating, ventilation, and air conditioning (HVAC) air-filter detection.
“With the addition of the new airflow ranges, Honeywell provides its customers with more options to integrate the sensor into their applications,” says A. J. Smith, director of global product marketing for Honeywell Sensing and Control. “Customers will also benefit from the portfolio’s industry-leading accuracy and the ability to customize the sensor to meet their specific application needs.”
Customers who have already designed a bypass that extends the flow range above the normal range of the existing airflow sensor can now use the Zephyr airflow sensor to optimize overall performance and reduce manufacturing costs.
Additional features include:
• Total error band as low as ±2.25-percent full scale span (FSS) allows for accurate airflow measurement
• Stability reduces errors due to thermal effects and null shift, providing accurate readings over time and often eliminating system calibration after PC board mount
• Linear output provides a more intuitive signal than the raw output of basic airflow sensors, helping to reduce production costs and design and implementation time
• Low pressure drop typically improves patient comfort in medical applications, and reduces noise and system wear on other components such as motors and pumps
Potential applications for the Zephyr airflow sensors include:
• Medical: anesthesia, hospital diagnostics (e.g., spectrometry and gas chromatography), nebulizers, oxygen concentrators, patient monitoring, sleep apnea, spirometers, ventilators, and ventricular assist devices
• Industrial: air-to-fuel ratio, analytical instrumentation (spectrometry, chromatography), fuel cells, gas leak detection, gas meters, HVAC filters, variable air volume (VAV) system on HVAC systems, and meteorology
Links:
[1] http://sensing.honeywell.com/honeywell%20zephyr%E2%84%A2%20analog%20airflow%20sensors%20%28haf%20series-high%20accuracy%29