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Kestrel 5400AG Livestock Heat Stress Tracker with LiNK + Vane Mount


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Regular price $699.00 USD

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Don’t let cattle heat stress reduce your herd performance and cost you money.

Implement an effective management plan based on objective and accurate THI, HLI and AHLU measurements at the pen level with Kestrel. Rugged hand-held meter can also be mounted with included hardware for longer term monitoring of heat events.

Kestrel 5400AG Cattle Heat Stress Tracker with LiNK + Vane Mount Overview

The Kestrel 5400 Cattle Heat Stress Tracker offers micro-climate measurement and monitoring at the pen or yard location. Contains a built-in Globe Temperature sensor and complete cattle-specific calculations. Measure THI and HLI and track AHLU based on easy-to-input herd and pen parameters. Perform spot checks or mount in place with the included vane mount accessory to track AHLU for months.  LiNK capability allows remote access to current and logged data from your iOS or Android mobile device. Mount a mobile data equipped tablet nearby to send mobile alerts even when you’re not on-site. Designed by Kestrel with input from some of the world’s most respected experts in cattle heat stress, the Kestrel 5400 Cattle Heat Stress Tracker is designed to help you MEASURE and MANAGE your herd’s heat stress, ensuring you MAXIMIZE your bottom line.

Environmental Measures

  • Altitude (Barometric)
  • Accumulated Heat Load Units (AHLU)
  • Barometric Pressure
  • Crosswind
  • Delta T
  • Density Altitude
  • Dew Point Temperature
  • Globe Temperature
  • Headwind/Tailwind
  • Heat Load Index (HLI)
  • Heat Stress Index
  • Naturally Aspirated Wet Bulb Temperature        
  • Relative Humidity
  • Station Pressure (Absolute Pressure)
  • Temperature
  • Temperature-Humidity Index (THI) 
  • Wet Bulb Temperature (Psychrometric)
  • Wet Bulb Globe Temperature (WBGT)
  • Wind Chill
  • Wind Direction (Cardinal Points, Degrees)
  • Wind Speed


  • Heat Load Index (HLI), Temperature-Humidity Index (THI), Accumulated Heat Load Units (AHLU), Wet Bulb Globe Temperature (WBGT), heat index, Delta T, temperature, humidity and much more. 21 measurements in all!
  • Complete weather station capabilities with a comprehensive suite of weather measurements including wind speed, direction, pressure trend, temperature and humidity.
  • Durable, portable, and easy to use data logger with customizable category settings, graphing and measurement statistics.
  • Large, hi-res, hi-contrast, graphic display is perfectly readable in the brightest sunlight and is backlit for use in low-light conditions.
  • LiNK connectivity powered by Bluetooth LE® provides wireless communication to mobile devices and computers.
  • Rugged (drop tested to MIL-STD-810G standards), dust and waterproof (sealed to IP67 standards).
  • Included Kestrel Vane Mount easily attaches to fencing.
  • Protective pouch, neck lanyard and Lithium AA battery included.
  • 5-year warranty.

Kestrel 5400AG Specifications and Dimensions

What's in the box?

  • 5400AG Meter
  • Kestrel Vane Mount
  • Neck Lanyard
  • AA Lithium Battery (Average Life 400 Hours)
  • Protective Drawstring Pouch
  • Certificate of Conformity (with complete specifications)
  • Instruction Manual 
  • Five Year Manufacturers Warranty

Compare All Livestock and Agriculture Models










Relative Humidity
Heat Stress Index
Temperature-Humidity Index (THI)
Dew Point Temp.
Wind Speed/Air Speed  
Wind Chill  
Wet Bulb Temp. (Psychrometric)  
Station Pressure (Absolute Pressure)  
Barometric Pressure  
Density Altitude  
Volume Air Flow    
Wind Direction    
Crosswind / Headwind / Tailwind    
Delta T    
Globe Temp.      
Naturally Aspirated Wet Bulb Temp.      
Wet Bulb Globe Temp. (WBGT)      
Heat Load Index (HLI)      
Accumulated Heat Load Units (AHLU)      

Wind Speed, Temperature, Barometric Pressure, Delta-T, Density Altitude, Dew Point Temperature, Globe Temperature, Heat Load Index (HLI), Heat Stress Index, Naturally Aspirated Wet Bulb Temperature, Relative Humidity, Temperature-Humidity Index (THI), WBGT (Wet Bulb Globe Temperature), Wet Bulb Temperature (Psychrometric), Wind Chill, and Wind Direction

(1) AAA Lithium Battery, Instructions, Protective Draw String Pouch, Lanyard, and Certificate Of Conformity (Spec Sheet)

Wind Speed |Air Larger of 3% of reading, least significant digit or 20 ft/min Speed 0.1 m/s
1 ft/min
0.1 km/h
0.1 mph
0.1 knots
1 B*
0.1 F/S*
0.6 to 40.0 m/s
118 to 7,874 ft/min
2.2 to 144.0 km/h
1.3 to 89.5 mph
1.2 to 77.8 knots
0 to 12 B*
1 inch|25 mm diameter impeller with precision axle and low-friction Zytel® bearings. Startup 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 startup. Off-axis accuracy -1% @ 5º off axis; -2% @ 10º; -3% @ 15º. 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). Wind speed calibration and testing should be done with triangle on impeller located at the top front face of the Kestrel. Measuring wind speeds above 60 m/s / 134.2 mph can damage the impeller
Ambient Temperature 0.9 °F
0.5 °C
0.1 °F
0.1 °C
-20.0 to 158.0 °F
-29.0 to 70.0 °C
Airflow of 2.2 mph|1 m/s or greater provides fastest response and reduction of insolation effect. For greatest accuracy, avoid direct sunlight on the temperature sensor and prolonged sunlight exposure to the unit in low airflow conditions. Calibration drift is negligible for the life of the product. For further details, see Display & Battery Operational Temperature Limits.
Globe Temperature 2.5 °F
1.4 °C
0.1 °F
0.1 °C
-20.0 to 140.0 °F
-29.0 to 60.0 °C
Temperature inside 1in|25 mm black powder coated copper globe converted to Tg equivalent for standard 6 in|150 mm globe. Closest equivalence obtained with airflow greater than 2.2 mph|1 m/s.
Relative Humidity 2%RH 0.1 %RH 10 to 90% 25°C noncondensing 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 is typically less than ±0.25% per year.
Pressure 1.5 hPa|mbar
0.044 inHg
0.022 PSI
0.1 hPa|mbar
0.01 inHg
0.01 PSI
700-1100 hPa|mbar
20.67-32.48 inHg
10.15-15.95 PSI
Monolithic silicon piezo-resistive pressure sensor with second-order temperature correction. Between 1100–1600 mbar, unit will operate with reduced accuracy. Sensor may not operate above 1600 mbar and can be damaged above 6,000 mbar or below 10 mbar. Calibration drift is negligible for the life of the product.
1/16th Cardinal Scale
0 to 360° 2-axis solid-state magneto-resistive sensor mounted perpendicular to unit plane. Accuracy of sensor dependent upon unit’s vertical position. Self-calibration routine eliminates magnetic error from batteries or unit and must be run after every full power- down (battery removal or change). Readout indicates direction to which the back of the unit is pointed when held in a vertical orientation. Declination/variation adjustable for True North readout.

AHLU AHLU Accuracy derived from HLI accuracy accumulated over time. 1.0 Wind Speed,
Temperature Globe Temperature,
Relative Humidity
Altitude typical: 23.6 ft/7.2 m
from 750 to 1100 mBar
max: 48.2 ft/14.7 m
from 300 to 750 mBar
1 ft 1 m Pressure,
User Input (Reference Pressure)
Barometric Pressure 0.07 inHg
2.4 hPa|mbar
0.03 PSI
0.01 inHg
0.1 hPa|mbar
0.01 PSI
Pressure, User Input (Reference Altitude)
Crosswind & Headwind/Tailwind 7.1% 1 mph
1 ft/min
0.1 km/h
0.1 m/s
0.1 knots
Wind Speed, Compass
Density Altitude 226 ft
69 m
1 ft 1 m Temperature, Relative Humidity Pressure
Dew Point 3.4 °F
1.9 °C
95% RH. Refer to Range for Temperature Sensor
0.1 °F
0.1 °C
Temperature, Relative Humidity
Heat Index 7.1°F
0.1 °F
0.1 °C
Temperature, Relative Humidity
HLI 2.7 1.0 Wind Speed, Temperature Globe Temperature, Relative Humidity
Outdoor Wet Bulb Globe Temperature (WBGT) 1.3 °F
0.7 °C
0.1 °F
0.1 °C
Wind Speed, Temperature Globe Temperature, Rative Humidity, Pressure
Probability of Ignition (PIG) PIG Accuracy dependent on proximity of inputs to reference table steps. 10% Temperature, Relative Humidity
THI (NRC) 1.5 °F
0.8 °C
0.1 °F
0.1 °C
Temperature, Relative Humidity
THI (Yousef) 2.3 °F
1.3 °C
0.1 °F
0.1 °C
Temperature, Relative Humidity
Thermal Work Limit (TWL) 10.9W/m2 0.1 °F
0.1 °C
TWind Speed,
Temperature Globe Temperature,
Relative Humidity,
Wet Bulb Temperature - Psychrometric 3.2 °F
1.8 °C
0.1 °F
0.1 °C
Temperature, Relative Humidity Pressure
Wet Bulb Temperature - Naturally Aspirated (NWB TEMP) 1.4 °F
0.8 °C
0.1 °F
0.1 °C
Wind Speed, Temperature Globe Temperature, Relative Humidity, Pressure
Wind Chill 1.6 °F
0.9 °C
0.1 °F
0.1 °C
Wind Speed, Temperature
Display & Backlight Multifunction, multidigit monochrome dot-matrix display. Choice of white or red LED backlight.
Response Time & Display Update Display updates every 1 second. After exposure to large environmental changes, all sensors require an equilibration period to reach stated accuracy. Measurements employing RH may require longer periods particularly after prolonged exposure to very high or very low humidity. WBGT requires about 8 minutes to reach 95% accuracy and about 15 minutes to reach 99% accuracy after exposure to large environmental changes.
Data Storage & Graphical display Min/Max/Avg History Logged history stored and displayed for every measured value. 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. Kestrel 5 series units hold over 10,000 data points.
data Upload & Bluetooth Data Connect Option Wireless range up to 100ft. Connection requires optional USB data transfer cable or Kestrel Link Dongle or Kestrel LiNK app. Employs Kestrel Link protocol for data transmission with Link supported devices. (Kestrel LiNK for iOS/Android, Kestrel Link for PC/MAC).
Clock/Calendar Real-time hours:minutes:seconds clock, calendar, automatic leap-year adjustment.
Auto Shutdown User-selectable – Off, 15-60 minutes with no key presses.
Languages English, French, German, Spanish.
Certifications CE certified, RoHS, FCC, IC tested and WEEE compliant. Individually tested to NIST-traceable standards.
Origin Designed and manufactured in the USA from US and imported components. Complies with Regional Value Content and Tariff Code Transformation requirements for NAFTA Preference Criterion B.
Battery Life AA Lithium included. Up to 400 hours of use, reduced by backlight, alert light and buzzer, or Bluetooth radio transmission use.
Shock Resistance MIL-STD-810g, Transit Shock, Method 516.6 Procedure IV; unit only; impact may damage replaceable impeller.
Sealing Waterproof (IP67 and NEMA-6)
Display & Battery Operational Temperature Limits 14° F to 131° F | -10 °C to 55 °C Measurements may be taken beyond the limits of the operational temperature range of the display and batteries by maintaining the unit within the operational range and then exposing it to the more extreme environment for the minimum time necessary to take reading.
Storage Temperature -22.0 °F to 140.0 °F | -30.0 °C to 60.0 °C.
Size & Weight 5.0 x 1.9 x 1.1 in | 12.7 x 4.5 x 2.8 cm, 4.3 oz | 121 g. (Lithium battery included)