testo 425 - Thermal Anemometer  | Velocity / air flow | CO,CO₂,light and sound | Parameters

In order to establish whether an air conditioning or ventilation system is functioning properly, among other things you need to check the flow speed or the volumetric flow in the ventilation duct. If the air flow velocity is too low, the room loads are not correctly discharged and optimum room air quality can no longer be guaranteed.

testo 425 thermal anemometer for quick, easy flow measurement

The testo 425 thermal anemometer enables quick spot measurements in ventilation ducts. It records the flow speed, calculates the volumetric flow and also measures the temperature. With a measuring range of 0 to +20 m/s, the anemometer is particularly well suited to low air flow velocity.
The thermal anemometer features a telescopic flow probe. The telescope can be extended to a length of up to 820 mm and has a probe head diameter of 7.5 mm.
As well as flow speed, would you also like to detect the volumetric flow on your air conditioning or ventilation system? This is no problem for the testo 425 thermal anemometer. When you input the duct surface area, it automatically calculates the volumetric flow during the flow measurement. Single and multi-point averaging provides an indicator of the average volumetric flow, flow speed and temperature reading.
You can read off the current readings and the min/max and calculated mean value at any time on the illuminated display. Using the Hold button, you can freeze the current reading in order to compare it with another value, for example. If you should ever forget to switch off the anemometer, the Auto-off function will take care of this for you. This conserves your batteries and ensures that your thermal anemometer is ready for use in the next measurement.

testo 425 thermal anemometer, Calibration protocol and battery

Temperature - NTC
Measuring range	-20 to +70 °C
Accuracy	±0.5 °C (0 to +60 °C) ±0.7 °C (Remaining Range)
Resolution	0.1 °C

Temperature - NTC

Measuring range

-20 to +70 °C

Accuracy

±0.5 °C (0 to +60 °C)

±0.7 °C (Remaining Range)

Resolution

0.1 °C

Velocity -Thermal anemometer
Measuring range	0 to +20 m/s
Accuracy	±(0.03 m/s + 5 % of mv)
Resolution	0.01 m/s

Velocity -Thermal anemometer

Measuring range

0 to +20 m/s

Accuracy

±(0.03 m/s + 5 % of mv)

Resolution

0.01 m/s

General technical data
Dimensions	182 x 64 x 40 mm
Operating temperature	-20 to +50 °C
Housing	ABS
Battery type	9V block battery, 6F22
Battery life	20 h
Storage temperature	-40 to +70 °C
Weight	285 g

General technical data

Dimensions

182 x 64 x 40 mm

Operating temperature

-20 to +50 °C

Housing

ABS

Battery type

9V block battery, 6F22

Battery life

20 h

Storage temperature

-40 to +70 °C

Weight

285 g

testo 425 - Thermal Anemometer

Product Description

testo 425 thermal anemometer for quick, easy flow measurement

Delivery Scope

Cases

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Manuals