Sensing and Control
 
Honeywell Zephyr™ Airflow Sensors - Product Overview

Honeywell is pleased to announce an extension to the Honeywell Zephyr™ Airflow Sensor product portfolio that extends the flow range from a previous flow range of 200 SCCM to new multiple flow ranges of ±50 SCCM to ±750 SCCM. This extended flow range allows customers that have already designed a bypass the ability to choose an airflow sensor to optimize their overall performance. A bypass is a path that is parallel to the main airflow channel that extends the flow range above the normal range of the airflow sensor.

 

Honeywell Zephyr™ Analog and Digital Airflow Sensors provide an analog or digital interface for reading airflow over the specified full-scale flow span and temperature range. The thermally isolated heater and temperature sensing elements help these sensors provide a fast response to air or gas flow.

 

Zephyr airflow sensors are designed to measure mass flow of air and other non-corrosive gases. The sensors are fully calibrated and temperature compensated with an onboard Application Specific Integrated Circuit (ASIC). They are compensated over the temperature range of 0 °C to 50 °C [32 °F to 122 °F] and operate across a temperature range of -20 °C to 70 °C [-4 °F to 158 °F]. The state-of-the-art ASIC-based compensation provides analog or digital (I2C) outputs with a response time of 1 ms.

 

Zephyr airflow sensors provide the customer with enhanced reliability, high accuracy, repeatable measurements and the ability to customize the sensor to meet many specific application needs. The combination of rugged housings with a stable substrate make these products extremely robust. They are designed and manufactured according to ISO 9001 standards.

Features and Benefits

( = competitive differentiator)

Total Error Band as low as ±2.25 %FSS: Allows for very precise airflow measurement, often ideal for demanding applications with high accuracy requirements
Wide range of airflows: 
- Detects the presence or absence of airflow from 50 SCCM up to 750 SCCM, increasing the options for integrating the sensor into the application
- High sensitivity at very low flows
- Full calibration and temperature compensation typically allow the customer to remove additional components associated with signal conditioning from the PCB, reducing PCB size as well as costs often associated with those components (e.g., acquisition, inventory, assembly)
Customizable: Allows customers to design the sensor to meet specific end-user needs
High stability: Reduces errors due to thermal effects and null shift to provide accurate readings over time, often eliminating the need for system calibration after PCB mount and periodically over 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
Linear output: Provides more intuitive sensor signal than the raw output of basic airflow sensors, which can help reduce production costs, design, and implementation time • Fast response time of 1 ms: Allows the customer's application to respond quickly to airflow change, important in critical medical (e.g., anesthesia) and industrial (e.g., fume hood) applications

• Fast response time of 1 ms: Allows the customer's application to respond quickly to airflow change, important in critical medical (e.g., anesthesia) and industrial (e.g., fume hood) applications
• 11-bit (analog version) or 12-bit (digital version) resolution: Increases the ability to sense small airflow changes, allowing customers to more precisely control their application
• Low 3.3 Vdc operating voltage option and low power consumption: Allow for use in battery-driven and other portable applications
• ASIC-based I2C digital output (digital version) compatibility: Eases integration to microprocessors or microcontollers, reducing PCB complexity and component count
• Bidirectional flow sensing capability: Eliminates the need for two airflow sensors, helping to reduce production costs and implementation time
• Insensitivity to mounting orientation: Allows customers to position the sensor in the most optimal point in the system, eliminating concern for positional effects
• Insensitivity to altitude: Eliminates customer-implemented altitude adjustments in the system, easing integration and reducing production costs by not having to purchase additional sensors for altitude adjustments
• Small size: Occupies less space on PCB, allowing easier fit and potentially reducing production costs; PCB size may also be reduced for easier fit into space-constrained applications
• RoHS-compliant materials: Meet Directive 2002/95/EC
 

Potential Applications

Medical

• Anesthesia delivery machines
• Ventricular assist devices (heart pumps)
• Hospital diagnostics (spectrometry, gas chromatography)
• Nebulizers
• Oxygen concentrators
• Patient monitoring systems (respiratory monitoring)
• Sleep apnea machines
• Spirometers
• Ventilators
 

Industrial

• Air-to-fuel ratio
• Analytical instrumentation (spectrometry, chromatography)
• Fuel cells
• Gas leak detection
• Gas meters
• HVAC filters
• VAV system on HVAC systems
• Meteorology