| Primary Measurement |
Units |
Resolution |
Accuracy (+/-) |
Range:
Max
Operational
Specification
(if less) |
Notes |
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 |
| 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 |
| Max/Avg Wind |
One-button clear and restart of Max Wind Gust and Average Wind measurement by powering down and restarting unit. |
| Display & Backlight |
Reflective 3 1/2 digit LCD. Digit height 0.36 in / 9 mm. Aviation green electroluminescent backlight (except in Kestrel 1000). 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. |
| 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 |
After 45 minutes of no key presses. |
| Certifications |
CE certified, RoHS and WEEE compliant. Individually tested to NIST-traceable standards (written certificate of tests available at additional charge). |
| Battery |
CR2032, one, included. Average life, 300 hours. Battery life reduced by backlight use in 2000 to 3500 models. |
| 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 |
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). |
| Colour Options |
Green |
