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testo 400 - Universal IAQ instrument

testo 400 Universal IAQ instrument
testo 400
testo 400 Universal IAQ instrument
testo 400 Universal IAQ instrument
testo 400 Universal IAQ instrument
testo 400 Universal IAQ instrument
testo 400 Universal IAQ instrument
Application testo 400
Application testo 400
Application testo 400
Application testo 400
Application testo 400
The testo 400 is the ultimate tool for professionals in indoor air quality (IAQ) measurement. It offers a wide range of features including intuitive measurement programs, high-precision sensors, and the ability to connect a variety of probes. It’s the ideal instrument for measuring, analysing, and documenting all IAQ and comfort parameters, providing full compliance with standards.
  • Comprehensive IAQ Measurement – Measures all IAQ parameters, including flow velocity, temperature, humidity, pressure, CO2, CO, and more.
  • Smart Measurement Programs – Intuitive programs for HVAC grid measurements (EN ISO 12599, ASHRAE 111), PMV/PPD, turbulence, and more.
  • Built-in Differential Pressure Sensor – High-precision, location-independent sensor for accurate measurements.
  • Extensible with Probes – Compatible with Bluetooth® and cable probes for flexible measurement options.
  • Data Management & Reporting – Includes analytical software for easy data analysis, reporting, and customer management.
The testo 400 is a highly advanced, universal IAQ instrument designed to support professionals in the fields of air conditioning, ventilation, and environmental monitoring. It allows users to measure, analyse, and document all IAQ and comfort parameters using a single, intuitive device. Whether you're working on air flow measurements, temperature and humidity levels, or assessing air quality, the testo 400 offers the versatility and accuracy required to get the job done.

With high-quality measuring technology and smart measurement assistants, the testo 400 supports a wide range of applications, from standard-compliant HVAC grid measurements to long-term monitoring of indoor air quality. Its built-in sensors for differential pressure and absolute pressure enable location-independent, highly precise measurements.

You can also connect the testo 400 with a broad range of compatible Bluetooth® and cable probes, making it flexible for any measurement task. This includes flow velocity, CO2 and CO, radiant heat, illuminance, and turbulence. It even integrates with the testo 420 volume flow hood to manage volume flow measurement at large air inlets and outlets.
The instrument also supports long-term monitoring via an IAQ data logger for continuous air quality measurements. Furthermore, the testo 400 offers smart features such as measurement programs tailored to specific standards (like EN ISO 7730 and ASHRAE 55), and customer management tools to help you work efficiently on-site.

For ease of use, it comes with a smart-touch display for quick, intuitive operation. Measurement results and reports can be sent directly via WLAN or Bluetooth®, and further analysis and documentation can be done using the testo DataControl PC software.

Ideal For
  • HVAC Professionals: Perfect for air flow, temperature, humidity, and ventilation system inspections.
  • Environmental Monitors: Helps ensure compliant indoor air quality in commercial or residential spaces.
  • Long-Term IAQ Monitoring: Offers the tools to measure and monitor IAQ over extended periods.

Temperature - NTC

Measuring range
-40 to +150 °C
Accuracy
±0.5 % of mv ±1 Digit (Remaining Range)
±0.4 °C ±1 Digit (+75 to +99.9 °C)
±0.2 °C ±1 Digit (-25 to +74.9 °C)
±0.4 °C ±1 Digit (-40 to -25.1 °C)
Resolution
0.1 °C

Temperature - TC Type K (NiCr-Ni)

Measuring range
-200 to +1370 °C
Accuracy
±(0.3 °C + 0.1 % of mv) ±1 Digit
Resolution
0.1 °C

Differential pressure (internal sensor) - Piezoresistive

Measuring range
0 to +200 hPa
Accuracy
±(0.1 hPa + 1.5 % of mv) ±1 Digit (25.001 to 200 hPa)
±(0.3 Pa + 1 % of mv) ±1 Digit (0 to 25 hPa)
Resolution
0.001 hPa
1 x testo 400 universal IAQ instrument, including transport case for air flow measurements, testo DataControl software, connection hose, mains unit with USB cable, calibration protocol and instruction manual.

Comfort probes

Food probes

Humidity probes

Pitot tubes

Pressure probes

Surface probes

Temperature probes

Velocity

IAQ measurements in the field of air conditioning and ventilation

  • High-precision, location-independent and built-in differential pressure sensor, smart and intuitive measurement programs for IAQ measurements in accordance with the standards, creation of documentation on site, reports, versatile combination options with IAQ probes

IAQ measurements in the field of air conditioning and ventilation

Custom-combine your Testo IAQ measuring instrument with IAQ probes and accessories for your application.
 
With the right products, you can handle all kinds of IAQ applications:
 
  • Air flow measurements: Flow measurements in ducts, at outlets and on filters as per EN ISO 12599 and ASHRAE 111
  • Comfort level measurements: Measurement of indoor air quality or turbulence as per EN ISO 7730 and ASHRAE 55, NET measurement as per DIN 33403, PMV/PPD as per EN ISO 7730 and ASHRAE 55, WBGT measurement as per DIN 33403 and EN ISO 7243
  • Measurements in laboratories and cleanrooms: Flow measurements in fume cupboards as per DIN EN 14175-3/-4, differential pressure measurements and laminar flow measurements in cleanrooms, humidity measurements in cleanrooms
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  • not available
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Testo Ltd
Newman Lane
GU34 2URAlton
HampshireUnited Kingdom
01420 544433

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