Kanomax KA25 Hot-Wire Anemometer with Air Flow Calculation

Overview

The Kanomax KA25 is a precision-engineered hot-wire anemometer designed for reliable, real-time measurement of air velocity and ambient temperature in HVAC commissioning, indoor air quality (IAQ) assessment, cleanroom validation, and industrial ventilation system audits. Based on constant-temperature anemometry (CTA), the KA25 employs a fine platinum wire sensor maintained at a stable overheat above ambient—enabling highly sensitive detection of convective heat loss proportional to airflow velocity. Unlike cup or vane anemometers, this thermal principle delivers superior low-velocity resolution (0.01 m/s) and rapid dynamic response (~1 s for 90% step response at 1 m/s), making it suitable for turbulent, low-flow, and bidirectional airstreams where mechanical inertia limits accuracy. Integrated temperature sensing (±0.5 °C accuracy above 0.5 m/s) and direct volumetric flow calculation—based on user-entered duct geometry (rectangular or circular cross-sections, dimensions from 0.1 to 255.0 cm)—enable immediate quantification of air volume in m³/h without external computation.

Key Features

• High-resolution hot-wire sensor with 0.01 m/s velocity resolution and extended range (0.01–20.0 m/s)
• Telescoping and bendable probe (Φ6 mm sensing tip, Φ14 mm ergonomic handle; 294–1060 mm adjustable length) for access to confined or irregular ductwork
• Real-time statistical analysis: simultaneous display of minimum, maximum, and average values over user-defined sampling intervals
• Configurable time constant (1 s / 5 s / 10 s / 20 s) to optimize responsiveness vs. signal smoothing per application requirement
• Three-level backlight LCD with intuitive icon-driven interface—designed for operation in low-light mechanical rooms or ceiling plenums
• Auto-hold function with manual data freeze and memory retention during measurement pauses
• Intelligent auto-power-off (selectable 3 / 5 / 10 minutes) to conserve battery life; estimated 15-hour runtime using standard AA alkaline cells
• Rugged, portable form factor (200 × 85 × 40 mm, ~220 g without batteries) with impact-resistant casing and included protective carry case

Sample Compatibility & Compliance

The KA25 is validated for use in clean, non-corrosive, particle-free air environments—consistent with ISO 14644-3 (cleanroom testing), ASHRAE Standard 111 (instrumentation for air system testing), and EN 13779 (ventilation for non-residential buildings). It is not rated for explosive atmospheres, high particulate loading (>1 mg/m³), or chemically aggressive gases (e.g., chlorine, ammonia, solvent vapors). The probe’s operating temperature range (−20 to +70 °C) and humidity tolerance (2–98% RH, non-condensing) support field use across diverse climatic conditions—from cold storage facilities to rooftop HVAC units. While not certified for FDA 21 CFR Part 11 compliance (as a standalone handheld instrument), its data logging and statistical functions align with GLP-aligned documentation practices when paired with traceable calibration records.

Software & Data Management

The KA25 operates as a self-contained, embedded-system instrument with no proprietary PC software or driver dependencies. All measurements—including velocity, temperature, calculated airflow, timestamps, and statistical aggregates—are displayed and retained locally on the device. Data export is performed manually via visual transcription or optional third-party digital capture (e.g., smartphone image logging). For regulated environments requiring audit trails, users are advised to implement supplementary procedural controls—such as standardized field logbooks, dated calibration certificates (traceable to JCSS or NIST-equivalent standards), and documented operator training—per ISO/IEC 17025 or internal QA protocols. Firmware updates are not supported; performance stability is ensured through factory calibration and sealed sensor architecture.

Applications

• HVAC balancing and commissioning: verification of supply/return/exhaust airflow across diffusers, grilles, and terminal units
• Cleanroom classification (ISO 14644-1): uniformity mapping and velocity profiling in laminar and non-uniform flow zones
• Industrial exhaust hood and fume cabinet face velocity surveys per ANSI/ASHRAE 110
• Building envelope infiltration assessment using tracer gas dilution or blower door auxiliary measurements
• Lab ventilation safety audits: sash face velocity checks, biosafety cabinet pre-use verification (in conjunction with manufacturer guidelines)
• Educational and research settings: fluid dynamics demonstrations, boundary layer studies, and airflow visualization correlation

FAQ

Is the KA25 suitable for measuring airflow in dusty or oily environments?
No. The hot-wire sensor is susceptible to contamination and drift when exposed to particulates, oil mist, or condensable vapors. It is intended exclusively for clean, dry air applications.
Can the KA25 measure bidirectional airflow (e.g., in return ducts with recirculation)?
Yes—the thermal anemometer detects magnitude and direction of convective cooling, enabling accurate low-velocity measurement regardless of flow direction, provided the probe is oriented perpendicular to the mean streamlines.
Does the KA25 include NIST-traceable calibration documentation?
Each unit ships with a factory calibration certificate issued by Kanomax Japan. For regulatory compliance, users must obtain periodic recalibration from an accredited laboratory (e.g., JCSS-certified providers) with documented uncertainty budgets.
What duct geometries does the built-in airflow calculator support?
Rectangular and circular cross-sections only. Users input height/width (cm) or diameter (cm), and the device computes volumetric flow (m³/h) using the averaged velocity and cross-sectional area.
Is the probe waterproof or washable?
No. The probe is not IP-rated. Avoid contact with liquids or cleaning solvents. Surface debris may be removed gently with dry, lint-free cloth or compressed air.