testo 405i – Smart Hot Wire Anemometer


No more surprises: the testo 405i thermal anemometer with smartphone operation from the Testo Smart Probes series is ideal for carrying out measuring tasks in ventilation ducts. It is easy to use the anemometer to determine air velocity, temperature and volume flows. The testo 405i is also suitable for measuring indoor air velocity. Practical when, for example, you want to locate non-airtight windows. Cooling capacities and heating outputs can also be calculated when used in conjunction with the testo 605i thermohygrometer.

Operation independent of measuring location via your smartphone

The testo 405i hot wire anemometer combines professional Testo measuring technology with App-based operation. This means you benefit from numerous additional functions in your day-to-day work. With the testo Smart Probes App, you can view readings conveniently on your smartphone or tablet. You no longer have to spend ages trying to make out the display at poorly accessible points. Volume flow can also be measured easily using the App: following intuitive input of the duct cross-section, the App calculates this completely automatically.

The App opens up other practical options too: it not only displays measurement data, but also evaluates and documents it. It is easy to carry out a timed and multi-point mean calculation with the App. It also displays the measurement data curve at the press of a button. And sends the measurement data logs as PDF or Excel files.

System requirements:
- iOS 8.3 or later
- Android 4.3 or later
- Bluetooth 4.0

More Information
Warranty2 Years
Technical Data
Instrument SensorHot wireNTC
Measuring range0 to 20 m/s-20 to +60 °C
Accuracy ±1 digit±(0.05 m/s + 2.5 % of m.v.) (0 to 2 m/s)
±(0.15 m/s + 2.5 % of m.v.) (2 to 15 m/s)
±0.5 °C
Resolution0.01 m/s0.1 °C
General Technical Data
CompatibilityRequires mobile end device with Bluetooth 4.0
Storage temperature-20 to +60 °C
Operating temperature-20 to +50 °C
Battery type3 micro batteries AAA
Battery life15 hrs
Dimensions200 x 30 x 41 mm
 Telescope extendable to 400 mm
What's Included

testo 405i, batteries and calibration protocol.

Measures air velocity, volume, flow and temp.

Extendable telescopic probe up to 400 mm

Easy set up for volume flow measurement via App

Report creation and transfer via smart phone.