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testo 350 - Analysis Box for exhaust gas analysis systems

0632 3510
  • Increased measurement range for unlimited measurements even when gas concentrations are higher
  • Easy-to-change gas sensors and easy access to wearing parts
  • Sealed housing with built-in impact protection for use in harsh conditions
  • Easy operation of the analyzer unit via Control Unit or easyEmission software (both products available separately) 
  • The testo 350 is a rugged, easy-to-use exhaust gas analyzer designed to meet the highest demands when it comes to carrying out precise industrial emission measurements and providing proper data administration. The Analysis Box can be operated with up to 6 gas sensors, 5 of which are optional. This allows you to select freely from sensors for CO, NO, NO2, SO2, H2S, CxHy and CO2.
    Ideal for professional flue gas analysis and industrial emissions measurement on industrial engines, burners, gas turbines and in thermal processes: the testo 350 flue gas analyzer performs a variety of measuring and analysis tasks, impresses over the long term thanks to its heavy-duty industrial design and is also suitable for complex data acquisition.


    The testo 350 flue gas analyzer comprises two units

    • The testo 350 Control Unit (separate product) with a clear graphic display, allows you to control emissions measurement. Operation is really easy: burner, gas turbine, engine and user-defined applications are available for selection in the menu. The Control Unit enables remote control of the analyzer unit even when there is a spatial separation of the flue gas pipe and the setting location – particularly recommended for emissions measurements on large plants.
    • The testo 350 analyzer unit is just what you need for carrying out emissions measurement, because it contains all the sensor technology and electronics. The testo 350 analyzer unit includes an O2 gas sensor as standard, but at least one additional sensor must be connected for commissioning (can be used with a maximum of 6 sensors). When connecting the optional sensors, you can choose between gas sensors for CO, CO2, NO, NO2, SO2, H2S or CxHy.

      The measuring range extension enables unrestricted measurements to be carried out, even when there are high gas concentrations. In order to protect the sensor technology, the measuring range extension (dilution) is automatically activated when there are unexpectedly high gas concentrations. The measuring range of a selected sensor can be extended by a specific factor. The service opening on the underside of the instrument allows fast access to all relevant serviceable and wearing parts, such as pumps and filters, enabling users to clean or replace these. In addition, the testo 350 has numerous instrument diagnosis functions. Instrument notifications are output in cleartext, making them easy to understand. The current status of the flue gas analyzer is constantly displayed.


      Using the testo 350 analyzer unit

      The analyzer unit can be operated with the Control Unit and it can also be used in direct combination with a PC/notebook and the easyEmission software (via USB, Bluetooth® 2.0 or CANCase). After programming, the analyzer unit can carry out measurements and save the results autonomously. It is also possible to display or transmit the measurement data from the analyzer unit to the Control Unit or software.

      To send the measurement report straight away, you can also use our free App which turns your Android smartphone or tablet into a display device for the analyzer unit.

    testo 350 analyzer unit, equipped with O2, including differential pressure sensor, temperature probe input type K NiCr-Ni and type S, Pt10Rh-Pt, Testo data bus connection, rechargeable battery, integrated combustion air probe (NTC), trigger input, measurement data memory, USB interface, carrying strap kit and calibration protocol.

    Please note: The testo 350 analyzer unit can only be used in combination with the testo 350 Control Unit or the "easyEmission" software. These items are available separately.

    Temperature - NTC

    Measuring range
    -20 to +50 °C
    ±0.2 °C (-10 to +50 °C)
    0.1 °C (-20 to +50 °C)
    Ambient temperature probe

    Temperature - TC Type K (NiCr-Ni)

    Measuring range
    -200 to +1370 °C
    ±1 °C (-200 to -100.1 °C)
    ±1 °C (200.1 to +1370 °C)
    ±0.4 °C (-100 to +200 °C)
    0.1 °C (-200 to +1370 °C)

    Temperature - TC Type S (Pt10Rh-Pt)

    Measuring range
    0 to +1760 °C
    ±1 °C (0 to +1760 °C)
    0.1 °C (0 to +1760 °C)

    Service measurement on gas turbines

    Gas turbines are subject to flue gas limit values which are to be adhered to during operation and regularly checked depending on the size of the system. After commissioning and maintenance work, the system's emission values are checked for adherence to limit values and also the manufacturer's specifications, and documented if necessary.

    Due to the low NO concentrations, emission measurements during inspection and adjustment work on LowNOx gas turbines need to be extremely accurate. The portable flue gas analyzer testo 350 featuring the combination of NO2 sensor and special NOlow sensor with a resolution of 0.1 ppm enables precisely these requirements to be met. In addition, the integrated gas preparation and special flue gas probe with patented special hose provide protection against NO2 absorption and allow measured values to be compared, irrespective of date and ambient conditions.

    testo 350

    Service measurement on industrial engines

    The flue (exhaust) gas analyzer testo 350 is an important tool for adjusting a gas or diesel engine to optimum effect. The testo 350 is used, for example, during commissioning, at regular maintenance intervals, or for troubleshooting unstable operational processes. Exhaust gas measurement is necessary to adjust the engine to optimum operating parameters while complying with the limit value regulations in force - this often entails measurements being taken over several hours. In particular, the high and fluctuating proportion of NO2 in the engine exhaust gas makes the separate measurement of NO and NO2 necessary to provide a highly accurate indication of the real NOx value of the engine. The integrated gas preparation and the special exhaust gas probe for industrial engines with patented special hose provide protection against NO2 and SO2 absorption and allow measured values to be compared, irrespective of date and ambient conditions.

    testo 350

    Service measurement on after treatment systems

    Restrictive limit values necessitate the use of a portable flue/exhaust gas analyzer to reliably determine the exhaust gas parameters in front of and after the after treatment system. In addition to the regular inspections for mechanical damage and contamination, the flue gas measurement provides information about the efficiency and functional reliability of a system. The bus function of the flue gas analyzer testo 350 allows flue/exhaust gas to be measured simultaneously in front of and after an exhaust after treatment system; this enables fast and easy assessment of the system. Any system modifications can be obtained from the measurement protocol.

    testo 350

    Analysis of the gas atmosphere (thermal processes)

    The flue gas analysis is used for thermal process monitoring in process combustion systems, such as in continuous furnaces for the glass, ceramics and construction material sector, or in steel melting and hardening furnaces, etc. In processes of this kind, substances may pass from the product being processed into the flue gas, increasing the usual emissions produced by the combustion system;

    vice versa, pollutants may pass from the gas and become part of the product being processed. The flue gas analyzer testo 350 can be used to pursue two main goals: monitoring of the process-related gas atmosphere to ensure the optimum quality of the processed products. The gas analysis provides information for process-related measures, such as the design of the furnace interior, flame control, fired product and furnace temperature, or the combustion air supply. At the same time, the gas analysis contributes to optimum operation of the system in terms of operating costs and safety.

    testo 350

    Service measurement on industrial burners

    For whichever purpose combustion systems are used, whether for heating, generating electrical power, steam or hot water, for the production or surface treatment of certain materials, or to incinerate waste and scrap materials, the best possible way of managing combustion and incineration definitely includes the right knowledge about the compositions of fuels and combustion air, and their relationship to one another. Even how they are combined is crucial. Mobile measuring technology allows all relevant gases to be analyzed and optimum combustion processes therefore to be achieved.

    The purpose of using a portable flue gas analyzer is to test the environmentally sound operation of combustion systems and optimum utilisation of the system. This means that a combustion system can be adjusted to its optimum working range to enable it to meet or come within stipulated emission limit values, while achieving a maximum level of efficiency in terms of combustion. The accurate flue gas analyzer testo 350, suited to tough practical conditions, is not only used for commissioning purposes, but also for repeat gas analyses during operation.

    testo 350

    Official emissions measurement (compliance testing)

    In most countries, operation of all types of industrial plants (e.g. large power stations, steelworks. cement works, glass works, and chemical plants), and local authority facilities, right through to small production sites is subject to strict regulations governing exhaust gas emissions into the atmosphere. Suitable measures are be taken to ensure and regularly verify that the components defined as pollutants do not exceed certain limit values in the flue gas.

    The flue gas analyzer testo 350 can be used to carry out a preliminary analysis before an official emissions reading, or, depending on the country and directive, the actual official compliance testing.

    testo 350

    • If the firmware update does not start under Windows 8.1 or Windows 10, a new bootloader must be installed on the measuring device once.
      A description and all necessary files can be found under the search term: Update-Kit / Bootloader
    • Update-Kit / Bootloader(V1.22, 1.24 MB)
      (testo 330 LL | testo 330i | testo 350 Control Unit + Analysis Box | testo 320)
      If the firmware update does not start under Windows 8.1 or Windows 10, a new bootloader must be installed on the measuring device once.