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Kestrel 3550AG Weather Meter for Spray Applications

Original price $299.00 - Original price $299.00
Original price
$299.00
$299.00 - $299.00
Current price $299.00

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Avoid spray drift and maximize application results with this portable and connected handheld weather meter. Off-target pesticide drift can not only cause damage to nearby vulnerable crops but also pose a serious threat to people, livestock, wildlife, and the surrounding community.

Farmers put themselves and their operations at risk every time they spray a field without documenting the wind speed and environmental conditions. The 3550AG with Bluetooth Connectivity makes it easy to instantly capture and log accurate, field-level weather data with just one-click.

Kestrel 3550AG Weather Meter for Spray Applications Overview

No matter the size of your operation -- effective herbicide and pesticide application is critical to your success. Prevent drift, eliminate waste, ensure safety and effectiveness – it all starts with monitoring your conditions.

Field-Level Environmental Monitoring for Reliable Decision-Making

It is critical to measure relative humidity, wind speed and wind direction at field-level to minimize waste and maximize safety when spraying. The on-site weather at time of application has a significant impact on the risk of drift. Best management practices include checking weather at the site of application to ensure safe and effective spraying. With a built-in digital compass, the 3550AG measures all relevant environmental conditions for spraying including wind direction.

Experts urge applicators to take measurements at the field location and make decisions from accurate, onsite information. It’s important to measure wind speed at the height of sprayer booms and not rely on readings from the local airport which could be dozens of miles away. The data from remote weather stations do not accurately reflect the conditions at your specific site.

Validation of current conditions meeting label requirements is every applicator’s priority and should be incorporated into all spraying application decisions. With the Kestrel 3550AG, you can easily monitor real-time weather conditions at the field-level.

Easy Record Keeping for Peace of Mind with the Free Kestrel App

As regulations surrounding drift management get tighter and media and public attention continues to increase, the stakes are higher than ever for applicators and farmers when it comes to accountability. It’s imperative to document spray conditions to defend against costly litigation and protect the future of your operation. The Kestrel app makes it easy to do by wirelessly connecting to the 3550 so you're able to view, log, and manage weather data on a mobile device. Now you can document field data right at the time of spray application -- forget pen and paper notes that can get lost or attempting to data log hours after the application when you’re back in the office and likely to forget. With just one click, the Snapshot feature in the app captures and saves an instant record of all live measurements along with a GPS-based timestamp. Conveniently export historical data as valuable documented evidence that you sprayed within acceptable weather conditions.

Pocket sized, rugged, waterproof, affordable, easy-to-use and equipped with on-unit data logging and wireless data retrieval for monitoring and reporting, the Kestrel 3550AG is your trusted weather guide for spraying and farming.

The new 3550AG meter has Bluetooth connectivity to pair with the Kestrel app for the ability to wirelessly view, share, and export weather data from a mobile device. Download the Kestrel app from the app store to take advantage of the all the features available.

Environmental Measures

  • Altitude (Barometric)
  • Barometric Pressure
  • Delta T
  • Dew Point Temperature
  • Heat Stress Index
  • Pressure Trend
  • Relative Humidity
  • Temperature Humidity Index (THI)
  • Temperature
  • Wet Bulb Temperature (Psychrometric)
  • Wind Chill
  • Wind Speed/Air Speed

Features

  • 3-Button Control
  • Backlight - Green
  • Data Hold Function
  • Date & Time
  • Drop-Tested to MIL-STD-810G
  • Field Humidity Calibration/Correction Routine
  • High Contrast, Sunlight Readable Monochrome LCD Display
  • Minimum/Maximum/Average Reading
  • Pressure Sensor
  • Relative Humidity Sensor
  • Temperature Sensor (Patented External Isolated)
  • Waterproof to IP67 (3'/1M for 30 minutes)

Includes

  • Battery - 1 x CR2032
  • Certificate Of Conformity (Spec Sheet)
  • Instructions
  • Lanyard
  • Protective Cover - Hard Slip-on
Specifications
SENSORS
SENSORS 1 0 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0 3 5 0 0 D T ACCURACY (+/-)* RESOLUTION SPEC. RANGE OP. RANGE NOTES
Wind Speed | Air Flow Larger of 3% of reading, least significant digit or 20 ft/min 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* 2-131.2 F/S* 0.6 to 60.0 m/s 118 to 11,811 ft/min 2.2 to 216.0 km/h 1.3 to 134.2 mph 1.2 to 116.6 knots 0 to 12 B* 2-196.9 F/S* 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. *F/S only in Ballistics units. Beaufort not available in Ballistics units.
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 14.0.0 to 131.0 °F -10.0 to 55.0 °C 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 insolation effect. Calibration drift negligible. Thermistor may also be used to measure temperature of water or snow by submerging thermistor portion into material -- remove impeller prior to taking submerged measurements and ensure humidity sensor membrane is free of liquid water prior to taking humidity-based measurements after submersion.
Relative Humidity 3.0 %RH 0.1 %RH 5 to 95% non-condensing 0 to 100% 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. Humidity sensor may be recalibrated at factory or in field using Kestrel Humidity Calibration Kit (NK PN-0802).
Pressure 1.5hPa|mbar 0.044 inHg 0.022 PSI 0.1 hPa|mbar 0.01 inHg 0.01 PSI 25°C/ 77°F 750-1100 hPa|mbar 22.15-32.48 inHg 10.88-15.95 PS 0.30 to 48.87 inHg 10.0 to 1654.7 hPa|mbar 0.14 to 24.00 PSI and 14.0 to 131.0 °F -10.0 to 55.0 °C Monolithic silicon piezoresistive pressure sensor with second-order temperature correction. Pressure sensor may be recalibrated at factory or in field. Adjustable reference altitude allows display of station pressure or barometric pressure corrected to MSL. Kestrel 4200 displays station pressure on a dedicated screen. 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. PSI display on Kestrel 4000 series only.
Compass 1° 1/16th Cardinal Scale 0 to 360° 0 to 360° 2-axis solid-state magnetoresistive 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.
CALCULATED MEASUREMENTS
MEASUREMENT 1 0 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0 3 5 0 0 D T ACCURACY (+/-)* RESOLUTION SPEC. RANGE SENSORS EMPLOYED NOTES
Altitude typical: 23.6ft/7.2m max: 48.2ft/14.7m 1ft 1m typical: 750 to 1100 mBar max: 300 to 750 mBar Pressure User Input (Reference Pressure) Height above Mean Sea Level ("MSL"). Temperature compensated pressure (barometric) altimeter requires accurate reference barometric pressure to produce maximum absolute accuracy. Both accuracy specs corresponds to a reference pressure anywhere from 850 to 1100 mBar.
Barometric Pressure 0.07 inHg 2.4 hPa|mbar 0.03 PSI 0.01 inHg 0.1 hPa|mbar 0.01 PSI Refer to Ranges for Sensors Employed Pressure User Input (Reference Altitude) Air pressure that would be present in identical conditions at MSL. Station pressure compensated for local elevation provided by reference altitude. Requires accurate reference altitude to produce maximum absolute accuracy
Delta T 3.2 °F 1.8 °C 0.1 °F 0.1 °C Refer to Ranges for Sensors Employed Temperature Relative Humidity Pressure Difference between dry bulb temperature and wet bulb temperature. When spraying, indicates evaporation rate and droplet lifetime. Safe range for pesticide spraying is 4 to 16 °F / 2 to 9 °C.
Dew Point 3.4 °F 1.9 °C 0.1 °F 0.1 °C 15 to 95 % RH Refer to Range for Temperature Sensor Temperature Relative Humidity Temperature that a volume of air must be cooled to at constant pressure for the water vapor present to condense into dew and form on a solid surface. Can also be considered to be the water-to-air saturation temperature.
Heat Index 7.1°F 4.0°C 0.1 °F 0.1 °C Refer to Ranges for Sensors Employed Temperature Relative Humidity Perceived temperature resulting from the combined effect of temperature and relative humidity. Calculated based on NWS Heat Index (HI) tables. Measurement range limited by extent of published tables
Wet Bulb Temperature - Psychrometric 1.6 °F 0.9 °C 0.1 °F 0.1 °C Refer to Ranges for Sensors Employed Temperature Relative Humidity Pressure Temperature indicated by a sling psychrometer. Due to nature of the psychrometric ratio for a water-air system, this approximates the thermodynamic wet-bulb temperature. The thermodynamic wet-bulb temperature is the temperature a parcel of air would have if cooled adiabatically to saturation temperature via water evaporating into it.
Wind Chill 1.6 °F 0.9 °C 0.1 °F 0.1 °C Refer to Ranges for Sensors Employed Wind Speed Temperature 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 10m above ground. Measurement range limited by extent of published tables.
ADDITIONAL SPECIFICATIONS
MEASUREMENT 1 0 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0 3 5 0 0 D T NOTES
Display & Backlight Reflective 3 1/2 digit LCD. Digit height 0.36 in / 9 mm. Aviation green electroluminescent backlight. Manual activation with auto-off
Reflective 5 digit LCD. Digit height 0.36 in / 9 mm. Choice of aviation green or visible red (NV models only) electroluminescent backlight. Manual activation with auto-off.
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.
Max/Avg Wind One-button clear and restart of Max Wind Gust and Average Wind measurement.
Data Upload & Bluetooth® Data Connect Option Requires optional PC interface (USB or RS-232) or Bluetooth data transfer option and provided software. Bluetooth Data Transfer Option: Adjustable power consumption and radio range from up to 30 ft | 9 meters. Individual unit ID and 4-digit PIN code preprogrammed for easy identification and data security when pairing and transmitting. Employs Bluetooth Serial Port Protocol for data transmission.
Clock / Calendar Real-time hours:minutes clock.
Auto Shutdown After 45 minutes of no key presses.
Languages English
Certifications CE certified, RoHS and WEEE compliant. Individually tested to NIST-traceable standards (written certificate of tests available at additional charge).
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 CR2032, one, included. Average life, 300 hours. Battery life reduced by backlight use in 2000 to 3500 models.
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).
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 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 4.8 x 1.9 x 1.1 in / 12.2 x 4.8 x 2.8 cm, 3.6 oz / 102 g (including slip-on cover).

* NOTE: Accuracy calculated as uncertainty of the measurement derived from statistical analysis considering the combined effects from primary sensor specifications, circuit conversions, and all other sources of error using a coverage factor of k=2, or two standard deviations (2Σ).

Trust Badge

Avoid spray drift and maximize application results with this portable and connected handheld weather meter. Off-target pesticide drift can not only cause damage to nearby vulnerable crops but also pose a serious threat to people, livestock, wildlife, and the surrounding community.

Farmers put themselves and their operations at risk every time they spray a field without documenting the wind speed and environmental conditions. The 3550AG with Bluetooth Connectivity makes it easy to instantly capture and log accurate, field-level weather data with just one-click.

Kestrel 3550AG Weather Meter for Spray Applications Overview

No matter the size of your operation -- effective herbicide and pesticide application is critical to your success. Prevent drift, eliminate waste, ensure safety and effectiveness – it all starts with monitoring your conditions.

Field-Level Environmental Monitoring for Reliable Decision-Making

It is critical to measure relative humidity, wind speed and wind direction at field-level to minimize waste and maximize safety when spraying. The on-site weather at time of application has a significant impact on the risk of drift. Best management practices include checking weather at the site of application to ensure safe and effective spraying. With a built-in digital compass, the 3550AG measures all relevant environmental conditions for spraying including wind direction.

Experts urge applicators to take measurements at the field location and make decisions from accurate, onsite information. It’s important to measure wind speed at the height of sprayer booms and not rely on readings from the local airport which could be dozens of miles away. The data from remote weather stations do not accurately reflect the conditions at your specific site.

Validation of current conditions meeting label requirements is every applicator’s priority and should be incorporated into all spraying application decisions. With the Kestrel 3550AG, you can easily monitor real-time weather conditions at the field-level.

Easy Record Keeping for Peace of Mind with the Free Kestrel App

As regulations surrounding drift management get tighter and media and public attention continues to increase, the stakes are higher than ever for applicators and farmers when it comes to accountability. It’s imperative to document spray conditions to defend against costly litigation and protect the future of your operation. The Kestrel app makes it easy to do by wirelessly connecting to the 3550 so you're able to view, log, and manage weather data on a mobile device. Now you can document field data right at the time of spray application -- forget pen and paper notes that can get lost or attempting to data log hours after the application when you’re back in the office and likely to forget. With just one click, the Snapshot feature in the app captures and saves an instant record of all live measurements along with a GPS-based timestamp. Conveniently export historical data as valuable documented evidence that you sprayed within acceptable weather conditions.

Pocket sized, rugged, waterproof, affordable, easy-to-use and equipped with on-unit data logging and wireless data retrieval for monitoring and reporting, the Kestrel 3550AG is your trusted weather guide for spraying and farming.

The new 3550AG meter has Bluetooth connectivity to pair with the Kestrel app for the ability to wirelessly view, share, and export weather data from a mobile device. Download the Kestrel app from the app store to take advantage of the all the features available.

Environmental Measures

  • Altitude (Barometric)
  • Barometric Pressure
  • Delta T
  • Dew Point Temperature
  • Heat Stress Index
  • Pressure Trend
  • Relative Humidity
  • Temperature Humidity Index (THI)
  • Temperature
  • Wet Bulb Temperature (Psychrometric)
  • Wind Chill
  • Wind Speed/Air Speed

Features

  • 3-Button Control
  • Backlight - Green
  • Data Hold Function
  • Date & Time
  • Drop-Tested to MIL-STD-810G
  • Field Humidity Calibration/Correction Routine
  • High Contrast, Sunlight Readable Monochrome LCD Display
  • Minimum/Maximum/Average Reading
  • Pressure Sensor
  • Relative Humidity Sensor
  • Temperature Sensor (Patented External Isolated)
  • Waterproof to IP67 (3'/1M for 30 minutes)

Includes

  • Battery - 1 x CR2032
  • Certificate Of Conformity (Spec Sheet)
  • Instructions
  • Lanyard
  • Protective Cover - Hard Slip-on
SENSORS
SENSORS 1 0 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0 3 5 0 0 D T ACCURACY (+/-)* RESOLUTION SPEC. RANGE OP. RANGE NOTES
Wind Speed | Air Flow Larger of 3% of reading, least significant digit or 20 ft/min 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* 2-131.2 F/S* 0.6 to 60.0 m/s 118 to 11,811 ft/min 2.2 to 216.0 km/h 1.3 to 134.2 mph 1.2 to 116.6 knots 0 to 12 B* 2-196.9 F/S* 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. *F/S only in Ballistics units. Beaufort not available in Ballistics units.
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 14.0.0 to 131.0 °F -10.0 to 55.0 °C 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 insolation effect. Calibration drift negligible. Thermistor may also be used to measure temperature of water or snow by submerging thermistor portion into material -- remove impeller prior to taking submerged measurements and ensure humidity sensor membrane is free of liquid water prior to taking humidity-based measurements after submersion.
Relative Humidity 3.0 %RH 0.1 %RH 5 to 95% non-condensing 0 to 100% 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. Humidity sensor may be recalibrated at factory or in field using Kestrel Humidity Calibration Kit (NK PN-0802).
Pressure 1.5hPa|mbar 0.044 inHg 0.022 PSI 0.1 hPa|mbar 0.01 inHg 0.01 PSI 25°C/ 77°F 750-1100 hPa|mbar 22.15-32.48 inHg 10.88-15.95 PS 0.30 to 48.87 inHg 10.0 to 1654.7 hPa|mbar 0.14 to 24.00 PSI and 14.0 to 131.0 °F -10.0 to 55.0 °C Monolithic silicon piezoresistive pressure sensor with second-order temperature correction. Pressure sensor may be recalibrated at factory or in field. Adjustable reference altitude allows display of station pressure or barometric pressure corrected to MSL. Kestrel 4200 displays station pressure on a dedicated screen. 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. PSI display on Kestrel 4000 series only.
Compass 1° 1/16th Cardinal Scale 0 to 360° 0 to 360° 2-axis solid-state magnetoresistive 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.
CALCULATED MEASUREMENTS
MEASUREMENT 1 0 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0 3 5 0 0 D T ACCURACY (+/-)* RESOLUTION SPEC. RANGE SENSORS EMPLOYED NOTES
Altitude typical: 23.6ft/7.2m max: 48.2ft/14.7m 1ft 1m typical: 750 to 1100 mBar max: 300 to 750 mBar Pressure User Input (Reference Pressure) Height above Mean Sea Level ("MSL"). Temperature compensated pressure (barometric) altimeter requires accurate reference barometric pressure to produce maximum absolute accuracy. Both accuracy specs corresponds to a reference pressure anywhere from 850 to 1100 mBar.
Barometric Pressure 0.07 inHg 2.4 hPa|mbar 0.03 PSI 0.01 inHg 0.1 hPa|mbar 0.01 PSI Refer to Ranges for Sensors Employed Pressure User Input (Reference Altitude) Air pressure that would be present in identical conditions at MSL. Station pressure compensated for local elevation provided by reference altitude. Requires accurate reference altitude to produce maximum absolute accuracy
Delta T 3.2 °F 1.8 °C 0.1 °F 0.1 °C Refer to Ranges for Sensors Employed Temperature Relative Humidity Pressure Difference between dry bulb temperature and wet bulb temperature. When spraying, indicates evaporation rate and droplet lifetime. Safe range for pesticide spraying is 4 to 16 °F / 2 to 9 °C.
Dew Point 3.4 °F 1.9 °C 0.1 °F 0.1 °C 15 to 95 % RH Refer to Range for Temperature Sensor Temperature Relative Humidity Temperature that a volume of air must be cooled to at constant pressure for the water vapor present to condense into dew and form on a solid surface. Can also be considered to be the water-to-air saturation temperature.
Heat Index 7.1°F 4.0°C 0.1 °F 0.1 °C Refer to Ranges for Sensors Employed Temperature Relative Humidity Perceived temperature resulting from the combined effect of temperature and relative humidity. Calculated based on NWS Heat Index (HI) tables. Measurement range limited by extent of published tables
Wet Bulb Temperature - Psychrometric 1.6 °F 0.9 °C 0.1 °F 0.1 °C Refer to Ranges for Sensors Employed Temperature Relative Humidity Pressure Temperature indicated by a sling psychrometer. Due to nature of the psychrometric ratio for a water-air system, this approximates the thermodynamic wet-bulb temperature. The thermodynamic wet-bulb temperature is the temperature a parcel of air would have if cooled adiabatically to saturation temperature via water evaporating into it.
Wind Chill 1.6 °F 0.9 °C 0.1 °F 0.1 °C Refer to Ranges for Sensors Employed Wind Speed Temperature 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 10m above ground. Measurement range limited by extent of published tables.
ADDITIONAL SPECIFICATIONS
MEASUREMENT 1 0 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0 3 5 0 0 D T NOTES
Display & Backlight Reflective 3 1/2 digit LCD. Digit height 0.36 in / 9 mm. Aviation green electroluminescent backlight. Manual activation with auto-off
Reflective 5 digit LCD. Digit height 0.36 in / 9 mm. Choice of aviation green or visible red (NV models only) electroluminescent backlight. Manual activation with auto-off.
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.
Max/Avg Wind One-button clear and restart of Max Wind Gust and Average Wind measurement.
Data Upload & Bluetooth® Data Connect Option Requires optional PC interface (USB or RS-232) or Bluetooth data transfer option and provided software. Bluetooth Data Transfer Option: Adjustable power consumption and radio range from up to 30 ft | 9 meters. Individual unit ID and 4-digit PIN code preprogrammed for easy identification and data security when pairing and transmitting. Employs Bluetooth Serial Port Protocol for data transmission.
Clock / Calendar Real-time hours:minutes clock.
Auto Shutdown After 45 minutes of no key presses.
Languages English
Certifications CE certified, RoHS and WEEE compliant. Individually tested to NIST-traceable standards (written certificate of tests available at additional charge).
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 CR2032, one, included. Average life, 300 hours. Battery life reduced by backlight use in 2000 to 3500 models.
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).
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 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 4.8 x 1.9 x 1.1 in / 12.2 x 4.8 x 2.8 cm, 3.6 oz / 102 g (including slip-on cover).

* NOTE: Accuracy calculated as uncertainty of the measurement derived from statistical analysis considering the combined effects from primary sensor specifications, circuit conversions, and all other sources of error using a coverage factor of k=2, or two standard deviations (2Σ).

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Avoid spray drift and maximize application results with this portable and connected handheld weather meter. Off-target pesticide drift can not only cause damage to nearby vulnerable crops but also pose a serious threat to people, livestock, wildlife, and the surrounding community.

Farmers put themselves and their operations at risk every time they spray a field without documenting the wind speed and environmental conditions. The 3550AG with Bluetooth Connectivity makes it easy to instantly capture and log accurate, field-level weather data with just one-click.

Kestrel 3550AG Weather Meter for Spray Applications Overview

No matter the size of your operation -- effective herbicide and pesticide application is critical to your success. Prevent drift, eliminate waste, ensure safety and effectiveness – it all starts with monitoring your conditions.

Field-Level Environmental Monitoring for Reliable Decision-Making

It is critical to measure relative humidity, wind speed and wind direction at field-level to minimize waste and maximize safety when spraying. The on-site weather at time of application has a significant impact on the risk of drift. Best management practices include checking weather at the site of application to ensure safe and effective spraying. With a built-in digital compass, the 3550AG measures all relevant environmental conditions for spraying including wind direction.

Experts urge applicators to take measurements at the field location and make decisions from accurate, onsite information. It’s important to measure wind speed at the height of sprayer booms and not rely on readings from the local airport which could be dozens of miles away. The data from remote weather stations do not accurately reflect the conditions at your specific site.

Validation of current conditions meeting label requirements is every applicator’s priority and should be incorporated into all spraying application decisions. With the Kestrel 3550AG, you can easily monitor real-time weather conditions at the field-level.

Easy Record Keeping for Peace of Mind with the Free Kestrel App

As regulations surrounding drift management get tighter and media and public attention continues to increase, the stakes are higher than ever for applicators and farmers when it comes to accountability. It’s imperative to document spray conditions to defend against costly litigation and protect the future of your operation. The Kestrel app makes it easy to do by wirelessly connecting to the 3550 so you're able to view, log, and manage weather data on a mobile device. Now you can document field data right at the time of spray application -- forget pen and paper notes that can get lost or attempting to data log hours after the application when you’re back in the office and likely to forget. With just one click, the Snapshot feature in the app captures and saves an instant record of all live measurements along with a GPS-based timestamp. Conveniently export historical data as valuable documented evidence that you sprayed within acceptable weather conditions.

Pocket sized, rugged, waterproof, affordable, easy-to-use and equipped with on-unit data logging and wireless data retrieval for monitoring and reporting, the Kestrel 3550AG is your trusted weather guide for spraying and farming.

The new 3550AG meter has Bluetooth connectivity to pair with the Kestrel app for the ability to wirelessly view, share, and export weather data from a mobile device. Download the Kestrel app from the app store to take advantage of the all the features available.

Environmental Measures

  • Altitude (Barometric)
  • Barometric Pressure
  • Delta T
  • Dew Point Temperature
  • Heat Stress Index
  • Pressure Trend
  • Relative Humidity
  • Temperature Humidity Index (THI)
  • Temperature
  • Wet Bulb Temperature (Psychrometric)
  • Wind Chill
  • Wind Speed/Air Speed

Features

  • 3-Button Control
  • Backlight - Green
  • Data Hold Function
  • Date & Time
  • Drop-Tested to MIL-STD-810G
  • Field Humidity Calibration/Correction Routine
  • High Contrast, Sunlight Readable Monochrome LCD Display
  • Minimum/Maximum/Average Reading
  • Pressure Sensor
  • Relative Humidity Sensor
  • Temperature Sensor (Patented External Isolated)
  • Waterproof to IP67 (3'/1M for 30 minutes)

Includes

  • Battery - 1 x CR2032
  • Certificate Of Conformity (Spec Sheet)
  • Instructions
  • Lanyard
  • Protective Cover - Hard Slip-on
SENSORS
SENSORS 1 0 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0 3 5 0 0 D T ACCURACY (+/-)* RESOLUTION SPEC. RANGE OP. RANGE NOTES
Wind Speed | Air Flow Larger of 3% of reading, least significant digit or 20 ft/min 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* 2-131.2 F/S* 0.6 to 60.0 m/s 118 to 11,811 ft/min 2.2 to 216.0 km/h 1.3 to 134.2 mph 1.2 to 116.6 knots 0 to 12 B* 2-196.9 F/S* 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. *F/S only in Ballistics units. Beaufort not available in Ballistics units.
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 14.0.0 to 131.0 °F -10.0 to 55.0 °C 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 insolation effect. Calibration drift negligible. Thermistor may also be used to measure temperature of water or snow by submerging thermistor portion into material -- remove impeller prior to taking submerged measurements and ensure humidity sensor membrane is free of liquid water prior to taking humidity-based measurements after submersion.
Relative Humidity 3.0 %RH 0.1 %RH 5 to 95% non-condensing 0 to 100% 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. Humidity sensor may be recalibrated at factory or in field using Kestrel Humidity Calibration Kit (NK PN-0802).
Pressure 1.5hPa|mbar 0.044 inHg 0.022 PSI 0.1 hPa|mbar 0.01 inHg 0.01 PSI 25°C/ 77°F 750-1100 hPa|mbar 22.15-32.48 inHg 10.88-15.95 PS 0.30 to 48.87 inHg 10.0 to 1654.7 hPa|mbar 0.14 to 24.00 PSI and 14.0 to 131.0 °F -10.0 to 55.0 °C Monolithic silicon piezoresistive pressure sensor with second-order temperature correction. Pressure sensor may be recalibrated at factory or in field. Adjustable reference altitude allows display of station pressure or barometric pressure corrected to MSL. Kestrel 4200 displays station pressure on a dedicated screen. 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. PSI display on Kestrel 4000 series only.
Compass 1° 1/16th Cardinal Scale 0 to 360° 0 to 360° 2-axis solid-state magnetoresistive 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.
CALCULATED MEASUREMENTS
MEASUREMENT 1 0 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0 3 5 0 0 D T ACCURACY (+/-)* RESOLUTION SPEC. RANGE SENSORS EMPLOYED NOTES
Altitude typical: 23.6ft/7.2m max: 48.2ft/14.7m 1ft 1m typical: 750 to 1100 mBar max: 300 to 750 mBar Pressure User Input (Reference Pressure) Height above Mean Sea Level ("MSL"). Temperature compensated pressure (barometric) altimeter requires accurate reference barometric pressure to produce maximum absolute accuracy. Both accuracy specs corresponds to a reference pressure anywhere from 850 to 1100 mBar.
Barometric Pressure 0.07 inHg 2.4 hPa|mbar 0.03 PSI 0.01 inHg 0.1 hPa|mbar 0.01 PSI Refer to Ranges for Sensors Employed Pressure User Input (Reference Altitude) Air pressure that would be present in identical conditions at MSL. Station pressure compensated for local elevation provided by reference altitude. Requires accurate reference altitude to produce maximum absolute accuracy
Delta T 3.2 °F 1.8 °C 0.1 °F 0.1 °C Refer to Ranges for Sensors Employed Temperature Relative Humidity Pressure Difference between dry bulb temperature and wet bulb temperature. When spraying, indicates evaporation rate and droplet lifetime. Safe range for pesticide spraying is 4 to 16 °F / 2 to 9 °C.
Dew Point 3.4 °F 1.9 °C 0.1 °F 0.1 °C 15 to 95 % RH Refer to Range for Temperature Sensor Temperature Relative Humidity Temperature that a volume of air must be cooled to at constant pressure for the water vapor present to condense into dew and form on a solid surface. Can also be considered to be the water-to-air saturation temperature.
Heat Index 7.1°F 4.0°C 0.1 °F 0.1 °C Refer to Ranges for Sensors Employed Temperature Relative Humidity Perceived temperature resulting from the combined effect of temperature and relative humidity. Calculated based on NWS Heat Index (HI) tables. Measurement range limited by extent of published tables
Wet Bulb Temperature - Psychrometric 1.6 °F 0.9 °C 0.1 °F 0.1 °C Refer to Ranges for Sensors Employed Temperature Relative Humidity Pressure Temperature indicated by a sling psychrometer. Due to nature of the psychrometric ratio for a water-air system, this approximates the thermodynamic wet-bulb temperature. The thermodynamic wet-bulb temperature is the temperature a parcel of air would have if cooled adiabatically to saturation temperature via water evaporating into it.
Wind Chill 1.6 °F 0.9 °C 0.1 °F 0.1 °C Refer to Ranges for Sensors Employed Wind Speed Temperature 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 10m above ground. Measurement range limited by extent of published tables.
ADDITIONAL SPECIFICATIONS
MEASUREMENT 1 0 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0 3 5 0 0 D T NOTES
Display & Backlight Reflective 3 1/2 digit LCD. Digit height 0.36 in / 9 mm. Aviation green electroluminescent backlight. Manual activation with auto-off
Reflective 5 digit LCD. Digit height 0.36 in / 9 mm. Choice of aviation green or visible red (NV models only) electroluminescent backlight. Manual activation with auto-off.
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.
Max/Avg Wind One-button clear and restart of Max Wind Gust and Average Wind measurement.
Data Upload & Bluetooth® Data Connect Option Requires optional PC interface (USB or RS-232) or Bluetooth data transfer option and provided software. Bluetooth Data Transfer Option: Adjustable power consumption and radio range from up to 30 ft | 9 meters. Individual unit ID and 4-digit PIN code preprogrammed for easy identification and data security when pairing and transmitting. Employs Bluetooth Serial Port Protocol for data transmission.
Clock / Calendar Real-time hours:minutes clock.
Auto Shutdown After 45 minutes of no key presses.
Languages English
Certifications CE certified, RoHS and WEEE compliant. Individually tested to NIST-traceable standards (written certificate of tests available at additional charge).
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 CR2032, one, included. Average life, 300 hours. Battery life reduced by backlight use in 2000 to 3500 models.
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).
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 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 4.8 x 1.9 x 1.1 in / 12.2 x 4.8 x 2.8 cm, 3.6 oz / 102 g (including slip-on cover).

* NOTE: Accuracy calculated as uncertainty of the measurement derived from statistical analysis considering the combined effects from primary sensor specifications, circuit conversions, and all other sources of error using a coverage factor of k=2, or two standard deviations (2Σ).

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