Kestrel 4200 Pocket Air Flow Tracker | RPR Ltd
Kestrel 4200 Pocket Air Flow Tracker
5-Year Warranty on all Kestrels

Kestrel 4200 Pocket Air Flow Tracker

Product code: K4200 - 0842

£0.00 inc. VAT

This product has now been superseded by the Kestrel 5200, which is available here »

The Kestrel 4200 Pocket Air Flow Tracker has been designed for HVAC applications, allowing instant and accurate readings of air flow and environmental conditions whenever and wherever you are.

Ideal for HVAC, health & safety, facilities and maintenance engineers, the Kestrel 4200 offers a multitude of features to help monitor your environment in one single instrument - right in the palm of your hand.

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The Kestrel 4200 combines all the features of the Kestrel 4000 and Kestrel 4100 (no longer available) and also makes the HVAC technicians job even easier with built-in wet bulb temperature and humidity ratio readings.

The Kestrel 4200 features automatic volume air flow readings. Simply enter the duct shape and dimensions, hold the Kestrel 4200 in the air stream and the volume air flow readings are displayed - no calculator required! With the convenient averaging mode, you can be sure the volume air flow readings are accurate in any airflow or duct size and shape.

Individual functions can be displayed in three different formats: current, minimum/maximum/average and chart. There are also three user screens, which can be customised to simultaneously display the three most appropriate functions for the application.

The Kestrel 4200 can be set up to log data automatically (as well as manually) at programmable intervals, in order to display a history of environmental information. Graphs display up to 3600 data points, the value, time and date of capture point can be shown.

The stored data can also be uploaded to a PC, for analysis/storage with the optional Kestrel Interface and Communicator software. With the Bluetooth model, data may be streamed live via Bluetooth wireless technology.

The display is easy to read with illumination for use in poor lighting conditions.

High precision Zytel bearings and a lightweight impeller provide accurate air flow measurements (+/-3% of reading) and the ability to operate at speeds as low as 0.6 m/s. The impeller is user-replaceable in case of damage, also ensuring high accuracy levels are maintained for life. An integral hard cover protects the impeller when not in use.

A precision external thermistor sensor provides fast response temperature readings and accuracy of +/- 1°C. The 0.1 degree resolution of the display aids in determining when a consistent reading has been reached. A special housing protects the relative humidity sensor from contamination providing an accuracy of +/-3%.

The Kestrel 4200 Pocket Air Flow Tracker is as accurate and comprehensive as other instruments costing far more. On-screen customisation allows the technician to personalise their 4200.

The Kestrel 4200 is powered by two easily replaceable AAA batteries and has two power saving modes to prolong battery life. All text can be displayed in one of five different languages: English, French, German, Italian or Spanish.

Kestrel 4200 measures
  • Volume air flow
  • Air velocity
  • Air temperature
  • Wind Chill
  • Heat index
  • Dew Point
  • Relative Humidity
  • Altitude
  • Barometric pressure
  • Density altitude
  • Time & Date
  • Wet bulb temperature
  • Choice of measurement units
  • m3/s, m3/min, m3/hr, l/s, ft3/min
  • kt, m/s, km/h, mph, ft/min, Beaufort
  • °C, °F
  • %
  • mbar, inHg, hPa, psi
  • m, ft
  • cm, m, in, ft (for duct size diameter or length & width)
  • Accuracy
  • Air flow ±3% of reading
  • Velocity ±3% of reading or ±0.1m/s
  • Temperature ±1°C
  • Relative humidity ±3%
  • Dew point ±2°C
  • Barometric pressure ±1.5mbar
  • Operational Range
  • Velocity 0.6 to 60 m/s
  • Temperature -45 to +125°C
  • Relative humidity 0 to 100%
  • Barometric pressure 10 to 1100mbar
  • Duct size dimension up to 6.55m
  • Specification Range
  • Velocity 0.6 to 40 m/s
  • Temperature -29 to +70°C
  • Relative humidity 5 to 95%
  • Barometric pressure 750 to 1100mbar
  • Available options
  • Bluetooth model
  • Kestrel 4200 features
    What makes a Kestrel Unique?
  • Multifunction instrument
  • Graphical three-line displays
  • Data capture up to 3600 readings
  • Minimum/maximum/average values
  • User defined screens
  • Language selection
  • Small robust design
  • High accuracy
  • High precision axle and low-friction Zytel bearings
  • Fast response temperature sensor
  • User replaceable impeller
  • Easy to read back-lit display
  • Hard cover protects impeller
  • Runs from 2 AAA batteries
  • Data upload (with optional PC interface or integrated Bluetooth wireless technology)
  • Available in safety orange
  • 5 year warranty
  • Typical applications
  • Heating and ventilation - air flow through fans, checking condition of filters
  • Industry - air flow measurements, pollution control
  • Primary Measurement Units Resolution Accuracy
    (if less)
    Wind Speed
    or Air Velocity
    m/s 0.1 Larger of 3% of reading, least significant digit or 20 ft/min 0.6 to 60.0 m/s
    0.6 to 40.0 m/s
    1 inch diameter impeller with precision axle and low-friction Zytel® bearings.
    Start-up speed stated as lower limit, readings may be taken down to 0.4 m/s | 79 ft/min | 1.5 km/h | .9 mph | .8 kt after impeller start-up.
    Off-axis accuracy -1% @ 5° off-axis; -2% @ 10°; -3% @ 15°.
    Calibration drift < 1% after 100 hours use at 16 MPH | 7 m/s.
    Replacement impeller (NK PN-0801) field installs without tools (US Patent 5,783,753).
    ft/min 1 18 to 11,811 ft/min
    118 to 7,874 ft/min
    km/h 0.1 2.2 to 216.0 km/h
    2.2 to 144.0 km/h
    mph 0.1 1.3 to 134.2 mph
    1.3 to 89.5 mph
    knots 0.1 1.2 to 116.6 knots
    1.2 to 77.8 knots
    Beaufort 1 0 to 12 B
    Temperature °F 0.1 1.8 °F -49.0 to 257.0
    -20.0 to 158.0
    Air, water or snow temperature. Hermetically-sealed, precision thermistor mounted externally and thermally isolated (US Patent 5,939,645) for rapid response. Airflow of 2.2 mph | 1 m/s or greater provides fastest response and reduction of insulation effect. Calibration drift negligible.
    °C 0.1 1.0 °C -45.0 to 125.0
    -29.0 to 70.0
    Relative Humidity %RH 0.1 3.0 %RH 0.0 to 100.0%
    5.0 to 95.0% non-condensing
    Polymer capacitive humidity sensor mounted in thin-walled chamber external to case for rapid, accurate response (US Patent 6,257,074). To achieve stated accuracy, unit must be permitted to equilibrate to external temperature when exposed to large, rapid temperature changes and be kept out of direct sunlight. Calibration drift +/- 2% over 24 months. RH may be recalibrated at factory or in field using Kestrel Humidity Calibration Kit (NK PN-0802).
    Pressure inHg 0.01 typical 0.04 inHg
    max 0.07 inHg
    0.30 to 32.48 inHg Air pressure at the location. Adjustable reference altitude allows display of station pressure or barometric pressure corrected to MSL. Monolithic silicon piezoresistive pressure sensor with second-order temperature correction. Pressure sensor may be recalibrated at factory or in field. Kestrel 2500 and 3500 display continuously updating three-hour barometric pressure trend indicator: rising rapidly, rising, steady, falling, falling rapidly. Kestrel 4000 series displays pressure trend through graphing function.
    hPa (mb) 0.1 typical 1.5 hPa
    max 2.5 hPa
    300.0 to 1100.0 hPa 10.0 to 1100.0 hPa
    PSI 0.01 typical 0.02 PSI
    max 0.04 PSI
    0.14 to 15.95 PSI
    Air Flow cfm 1 Larger of 3% of reading, least significant digit or 20 ft/min 0 to 99,999 cfm Volume of air flowing through an opening. Automatically calculated from Air Velocity measurement and user-specified duct shape (circle or rectangle) and dimensions (units: in, ft, cm or m). Maximum duct dimension input: 258.0 in | 21.5 ft | 655.3 cm | 6.55 m.
    m3/hr 1 0 to 99,999 m3/hr
    m3/m 1 0 to 99,999 m3/m
    m3/s 0.1 0.0 to 9,999.9 m3/s
    L/s 1 0 to 99,999 L/s
    Wind Chill °F 0.1 1.8 °F Refer to stated ranges for wind speed and temp. Perceived temperature resulting from combined effect of wind speed and temperature. Calculated based on the NWS Wind Chill Temperature (WCT) Index, revised 2001, with wind speed adjusted by a factor of 1.5 to yield equivalent results to wind speed measured at 10 m above ground. Specification temperature limits established by WCT Tables.
    °C 0.1 1.0 °C
    Heat Index °F 0.1 3.6 °F Refer to stated ranges for temp. and relative humidity. Perceived temperature resulting from the combined effect of temperature and relative humidity. Calculated based on NWS Heat Index (HI) tables. (Specification temperature limits established by HI tables.)
    °C 0.1 2.0 °C
    Wet Bulb Temperature (Psychrometric) °F 0.1 3.6 °F Refer to stated ranges for temp., relative humidity and pressure. Temperature indicated by a wet bulb psychrometer under forced aspiration. Calculated from temperature, relative humidity and pressure.
    °C 0.1 2.0 °C
    Dewpoint °F 0.1 3.6 °F Refer to stated ranges for temp. and relative humidity. Temperature to which the air must be cooled at a constant pressure for water vapour to condense into water. Calculated from temperature and relative humidity.
    °C 0.1 2.0 °C
    Altitude ft1 typical 50 ft
    max 98 ft
    -2,300 to 85,000 ft Height above Mean Sea Level ("MSL"). Temperature compensated pressure (barometric) altimeter requires accurate reference barometric pressure to produce maximum absolute accuracy.
    m 1 typical 15 m
    max 30 m
    -700 to 25,900 m
    Density Altitude ft 1 246 Refer to stated ranges for temp., relative humidity and pressure. Air density converted to equivalent sea level elevation at the International Standard Atmosphere. Calculated from temperature, pressure and relative humidity.
    m 1 75
    Max/Avg Wind Max and average wind calculation may be started and stopped independently of data logging of other values, along with all other wind-related functions: air velocity, crosswind, headwind/tailwind, wind chill, WBGT, TWL, evaporation rate.
    Data Storage & Graphical Display, Min/Max/Avg History Minimum, maximum, average and logged history stored and displayed for every measured value. Large capacity data logger with graphical display. Manual and auto data storage. Min/Max/Avg history may be reset independently. Auto-store interval settable from 2 seconds to 12 hours, overwrite on or off. Logs even when display off except for 2 and 5 second intervals (code version 4.18 and later). Data set capacity = 3600.
    Data Upload Requires optional PC interface (USB or RS-232) or Bluetooth enabled model and provided software.
    Available Bluetooth®
    Data Connect
    Adjustable power consumption and radio range from up to 30 ft | 9 meters. Individual unit ID and 4-digit PIN code pre-programmed for easy identification and data security when pairing and transmitting. Employs Bluetooth Serial Port Protocol for data transmission.
    Display & Backlight Multifunction, multi-digit monochrome dot-matrix display. Choice of aviation green or visible red (NV models only) electroluminescent backlight. Automatic or manual activation.
    Response Time & Display Update All measurements except those based on relative humidity respond accurately within 1 second. Relative humidity and all measurements which include RH in their calculation may require as long as 1 minute to fully equilibrate to a large change in the measurement environment. Display updates every 1 second.
    Clock / Calendar
    Real-time hours:minutes:seconds clock, calendar, automatic leap-year adjustment.
    Operational & Storage Temperature Range The operational temperature range of the liquid crystal display and batteries is 14° F to 131° F / -10 °C to 55 °C. Measurements beyond the operational range can be taken by briefly exposing unit to extreme conditions such that the display and batteries remain within the operational range. Storage range -22 °F to 140 °F / -30 °C to 60 °C.
    Auto Shutdown User-selectable -- 15 or 60 minutes with no key presses or disabled.
    Languages English, French, German, Italian, Spanish.
    Certifications CE certified, RoHS and WEEE compliant. Individually tested to NIST-traceable standards (written certificate of tests available at additional charge).
    Battery AAA Alkaline, two, included. Average life, 400 hours of use, reduced by backlight or Bluetooth radio transmission use.
    Environmental Waterproof (IP67 and NEMA-6). MIL-STD-810F, Transit Shock, Method 516.5 Procedure IV; unit only; impact may damage replaceable impeller.
    Size & Weight 5.0 x 1.8 x 1.1 in / 12.7 x 4.5 x 2.8 cm, 3.6 oz / 102 g.
    Colour Options Safety Orange

    The manufacturer reserves the right to amend the specification and therefore the information in this document may be subject to change