 Flexibility to Meet Your Applications
TSI's Air Velocity Transducers provide the flexibility you need for your air velocity measurement applications.
Three different sensor types and four standard probe lengths let you configure the transducer for your measurement needs. The transducers' full-scale range, output and time constants are user selectable for additional flexibility. The microprocessor-based design makes it easy to use with simple menu selections.
See also the Transducer Display and Monitor
Overview
Uses Thermal Anemometry
Backed by TSI Expertise
Measurement Dependability Three Ways
How It Works
Specifications
How To Specify
Downloads
(Brochures, Manuals, etc. Use your browser's back button to return)
Overview
Allowing for field selection of the full-scale velocity range, time constant and output signal means you can set-up the transducer for your specific application. You can select the full scale velocity range to maximize the output resolution, and change the full scale setting when your measurement needs change. The selectable time constant lets you use a long time constant to obtain stable readings in turbulent or fluctuating flows, or a short time constant for fast response. You can use current outputs for transmitting to a device located a distance from the transducer, or voltage outputs to interface to a computer.
Uses Thermal Anemometry
TSI uses the proven technology of thermal anemometry for accurate and reliable measurements. This means you can measure air velocity over a wide dynamic range with a fast response time. An additional advantage
of thermal anemometry is its accuracy at low velocities.
Backed by TSI Expertise
TSI Incorporated has more than 30 years experience in thermal anemometry and flow measurement technology.
It's this type of experience and innovation that provides you with accurate and reliable air velocity measurements.Each air velocity transducer's calibration is NIST* traceable. A certificate of calibration is included with each instrument.
*U.S. National Institute of Standards and Technology
Measurement Dependability Three Ways
With TSI's transducers, not only are you assured of reliable and accurate air velocity measurements, you can also
select the type of sensor that meets your individual measurement needs. You can choose between three different
models: General Purpose, Windowless and Omnidirectional.
|
General Purpose (8455)
|
Windowless (8465)
|
Omnidirectional (8475)
|
- Protected probe tip
- Rugged ceramic sensor
- Wide range of measurement applications
- Fast response time
|
- Less flow blockage
- Ideal for measuring in confined spaces
- Fast response time
|
- Omnidirectional probe tip
- Measures low velocities down to 0.05 m/s (10 ft/min)
- Ideal for unknown or varying flow direction
|
How It Works
The basic technology of the TSI Air Velocity Transducers is constant temperature thermal anemometry. It's known
as thermal anemometry because the sensor element contains a heated wire. A bridge circuit maintains the sensor
element at a constant temperature regardless of the air velocity.More power is required to maintain the sensor's temperature as the air velocity past the sensor increases.
Therefore, the power dissipated by the sensor is directly related to air velocity. TSI sensors are temperature
compensated. The transducers incorporate a temperature sensor to compensate for changes in air temperature. The transducer output is linear for user convenience. Built-in electronics read the sensor signal and linearize it using calibration data stored in memory. The digital method offers increased accuracy over the instrument's dynamic range.
You simply position the sensor in the flow to make the measurement, the transducer does the rest.
Specifications - Air Velocity Transducer Models 8455, 8465, 8475
SPECIFICATIONS UNIQUE TO SPECIFIC MODELS
|
8455
|
8465
|
8475
|
| Accuracy7 |
±2.0% of reading1
±0.5% of full scale of selected range |
±2.0% of reading1
±0.5% of full scale of selected range |
±3.0% of reading2
±1.0% of full scale of selected range |
| Repeatability |
<±1.0% of reading3 |
<±1.0% of reading3 |
N/A |
| Response Time to Flow
|
0.2 sec4 |
0.2 sec4
|
5.0 sec5 |
SPECIFICATIONS COMMON TO ALL MODELS
Field Selectable Velocity Ranges
Model 8455/8465 0.125 m/s to 1.0, 1.25, 1.50, 2.0, 2.5, 4.0, 5.0, 7.5, 10.0, 12.5, 15.0, 20.0, 25.0, 30.0, 40.0, 50.0 m/s (25 ft/min to 200, 250, 300, 400, 500, 750, 1000, 1250, 1500, 2000, 2500, 3000, 4000, 5000, 7500,
10000 ft/min)
Model 8475 0.05 m/s to 0.5, 0.75, 1.00, 1.25, 1.50, 2.0, 2.5 m/s (10 ft/min to 100, 125, 150, 200, 250, 300, 400, 500 ft/min)
Minimum Resolution 0.07% of selected full scale
Input Power 11-30 VDC or 18-28 VAC, 350 mA max6
Output Impedance Voltage mode: less than 1 ohm, 20 mA max source current
Output Resistance Current mode: 500 ohms maximum load resistance
Output Signal
(field selectable) 0-5V, 0-10V, 1-5V, 2-10V, 0-20mA, 4-20mA
Output Time Constant
(field selectable) 0.05 to 10 seconds
Probe Length 7.5 cm, 15 cm, 22.5 cm or 30 cm (3 in, 6 in, 9 in or 12 in)
Temperature Range
Compensation Range: 0 to 60°C (32 to 140°F)
Sensor Operation: 0 to 93°C (32 to 200°F)
Electronics Operation: 0 to 93°C (32 to 200°F)
Storage: 0 to 93°C (32 to 200°F)
1 From 18 to 28 °C (64.4 to 82.4 °F), outside this range add 0.2% per °C (0.4 per °F), within temperature compensation range.
2 From 20 to 26 °C (68 to 78.8 °F), outside this range add 0.5% per °C (0.9 per °F), within temperature compensation range. Directional sensitivity of the Model 8475 is +5%/-20% of reading +0/0.05 m/s (+0/-10 ft/min) over 270° solid angle regardless of flow direction.
3 Standard deviation, based on one minute average from 0.5 to 5.0 m/s (100 to 1000 ft/min).
4 For 63% of final value, tested at 7.5 m/s (1500 ft/min).
5 For 63% of final value, tested at 2.5 m/s (500 ft/min).
6 Input voltage must be maintained within specifications at the transducer.
7 Calibration occurs with sensor oriented horizontally in a horizontal air flow. Uncertainty increases in downward vertical flow at velocities less than 0.25 m/s (50 ft/min).
All specifications subject to change without notice.
How To Specify:
_ _ _ _ - _ _ _ -1 (Model number followed by probe length
followed by a and a 1)
Model Number -- 8455 = General Purpose
8465 = Windowless
8475 = Omnidirectional
Probe Length -- 075 = 7.5 cm (3 in.) probe
150 = 15.0 cm (6 in.) probe
225 = 22.5 cm (9 in.) probe 300 = 30.0 cm (12 in.) probe
Examples: 8465-215-1 = Windowless Velocity Transducer, 21.5 cm Probe
8455-150-1 = General Purpose Velocity Transducer, 15 cm Probe
8475-075-1 = Omnidirectional Velocity Transducer, 7.5 cm Probe
|
