Hot Wire Anemometer

Provides Precise Measurements of Air Flow, Velocity and Temperature. 


TSI's VELOCICALC® Air Velocity Meters are easy to use from the first time you pick them up. The Models 8345 and 8346 measure velocity and temperature, calculate flow rate, perform multi-value averaging, and determine minimum and maximum readings. The Models 8347 and 8347(A) add a humidity measurement and perform dew point and wet bulb temperature calculations. 

For more information on the Hot Wire Anemometer, contact your local Air-Met office. 

  • Extended velocity range of 0 to 6,000 ft/min
  • Temperature range of 0 to 140°F or more
  • Humidity range of 0 to 95% rh (Models 8347 and 8347(A) only)
  • Easy to read digital display
  • Variable time constant modes available for a steady display when measuring fluctuating flows
  • Telescoping probes with etched length marks to make duct traverse measurements easier
  • Sampling function allows for easy recording of multiple measuring points
  • Direct calculation of dew point and wet bulb temperature–no psychrometric chart needed (Models 8347 and 8347(A) only)
  • Statistics function can display average, maximum and minimum values, and the number of recorded samples
  • Flow rate feature allows for simple and quick calculations of volumetric flow rate when the user inputs the duct shape and size
Range:  0 to 6000 ft/min (0 to 30 m/s)
Accuracy1&2 3.0% of reading or ±3 ft/min (±0.015 m/s), whichever is greater
Range (8345/46):  0 to 200 ?F (-17.8 to 93.3 ?C)
Range (8347/47A):  14 to 140 ?F (-10 to 60 ?C)
Resolution:  0.1 ?F (0.1?C)
Accuracy3 ±0.5 ?F (±0.3 ?C)
Instrument Temperature Range: 
Operating (Electronics):  40 to 113 ?F (5 to 45 ?C)
Storage:  -22 to 194 ?F (-30 to 90 ?C)
Volumetric Flowrate: 
Range4 0.1 to 195,000 l/s, 0.0424 to 702,000 m3/hr, 0.2 to 2,700,000 ft3/min
Relative Humidity (MODELS 8347/8347A):
Range:  0 to 95% RH
Accuracy5: 5: ±3% RH
Resolution:  0.1% RH
Wet Bulb Temperature (MODELS 8347/8347A):
Range:  40 to 140°F (5 to 60°C)
Resolution:  0.1°F (0.1°C)
Dew Point (MODEL 8347/8347A):
Range:  5 to 120°F (-15 to 49°C)
Resolution:  0.1°F (0.1°C)
Duct Size: 
Range:  1 to 100 inches in increments of 0.5 inches, 100 to 255 inches in increments of 1 inch (1 to 100 cm in increments of 0.5 cm, 100 to 255 cm in increments of 1 cm)
Averaging Capability: 
Range:  Up to 255 values of each velocity (or flowrate), temperature, humidity, dew point temperature, and wet bulb temperature
Time Constant: 
Range:   Adjustable from 1 to 20 seconds
Response Time: 
To Velocity:  200 msec
To Temperature: 8345/46: 8 seconds
8347/47A: 34 seconds
External Meter Dimensions: 
Size Measurements:  3.9 in. x 6.6 in. x 1.5 in. (10 cm x 16.8 cm x 3.8 cm)
Meter Probe Dimensions:
Probe Length (8345):  37 in. (94 cm) telescopic
Probe Length (8346):  37 in. (94 cm) telescopic articulating
Probe Length (8347):  40 in. (102 cm) telescopic
Probe Length (8347A):  40 in. (102 cm) telescopic articulating
Meter Weight Dimensions:
Weight (with batteries):  1.1 lbs (0.5 kg)
Meter Display Dimensions: 
Display:  4-digit LCD, 0.6 in. (15 mm) digit height
Power Requirements:  Four AA-size batteries (included) or AC adapter (optional)
Printer Interface: Type Serial
Baud Rate 1200
1 Temperature compensated over an air temperature range of 40 to 150°F (5 to 65°C).
2 The accuracy statement of 3.0% of reading or ±3 ft/min (±0.015 m/s), applies to 30 ft/min
through 6,000 ft/min.
3 Accuracy with instrument case at 77°F (25°C), add uncertainty of 0.03°C/°C
(0.05°F/°F) for change in instrument temperature.
4 Actual range is a function of maximum velocity and duct size.
5 Accuracy with probe at 77°F (25°C). Add uncertainty of 0.1% rh/°F (0.2% rh/°C)
for change in probe temperature. Includes 1% hysteresis.
Specifications are subject to change without notice.
  • HVAC Industry
  • Excellent for measurements in turbulent flows
  • Measurements in restricted spaces
  • Fume hood face velocity tests
  • Clean room studies
  • Wind tunnel work
  • Filter face velocity measurements
  • Indoor air quality tests