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Emission Analyzer
testo 350
testo 350 Analyzer Definitions
Analyzer Box Condensate Trap Control Unit Dilution System Excess Air (ExA) Fresh Air Purge / Valve Function Keys Hydrogen Compensated CO Sensor Flow and Mass Flow Non-Heated Sample Line (testo Patented) (NO2/SO2-Hose) O2 Reference Over-Range Protection Pellister (CxHy Sensor) Peltier Cooler Pitot Tube Power / Battery / AC Operation testo-Databus Trigger Input / Switch Upgrade Module  Analyzer Box The Analyzer Box (testo 350) is a rugged plastic housing that contains the: sensors, pumps, gas conditioning system (Peltier chillier and pump), valves, electronics, etc, The Analyzer Box also contains a complete operating system that enables it to be used as a stand alone device that can be programmed to log measurements (250, 000 readings) for automatic semi continuous operation. The Analyzer Box can also be operated remotely (to 3000 ') with a data bus cable, or in a more traditional sense, with the "control unit docked" as a suitcase analyzer. Condensate Trap A clear acrylic container located on the side of the Analyzer Box that serves as a reservoir for condensate. The condensate water can be removed by 1) opening the plug, 2) attaching a hose to the drain port, or 3) by removing the condensate trap. Remove the trap by pulling the trap away from the analyzer and drain by shaking the trap. Control Unit The hand-held Control Unit "S" is the interface used to operate the Analyzer Box. The Control Unit houses: system software, a user-defined back lit display, a thermal paper printer and connection ports. Complete analyzer control is through the handheld. Dilution System A system that expands the range of the CO sensor by introducing a specific volume of "dilution air" through a precision valve assembly. The dilution system exclusively operates with the CO sensor. Dilution factors (1, 2, 5, 10, 20 or 40) are selected by the user by pushing a function button. The values are automatically calculated based upon the factor. The benefits of the dilution system include:
A calculated value that determines the amount of "extra" oxygen in a typical burner / boiler application. The analyzer will display a percentage of oxygen above the "perfect" (or stoichiometric) condition for complete combustion. In general, excess air dilutes and cools the combustion process, it absorbs the energy (heat), and reduces the efficiency of the combustion process Fresh Air Purge / Valve The purge valve (standard part on testo 350 XL) mechanically opens the fresh-air gas path to remove flue gases from the analyzer. This fresh-air purge is required for electrochemical sensors in order to have accurate response and long sensor life. This valve provides a means to perform long-term testing by maintaining electrolytic equilibrium within the sensor. Fresh air purges nearly eliminate sensor drift and saturation due to long term testing or high concentration loading The valve offers a side benefit that allows the flue gas probe to remain in the stack during analyzer start up or during automatic tests. By pushing the function button, the fresh air valve immediately pulls in air from the side of the analyzer. The days of climbing the stack and fumbling with the probe are gone. Function Keys Four round blue buttons located directly below the display of the Control Unit. Each user-defined function key provides a shortcut to important analyzer functions. Some example include: Start sample "Pump", or "Print" emission results, or transfer the measurement values into the memory "mem", etc. Hydrogen Compensated CO Sensor A standard electrochemical CO sensor will show a response to Hydrogen. Hydrogen can be in high concentration when excess air is low. testo sensors use an additional electrode in the sensor to measure the hydrogen and electronically compensate for this cross interfearent. This is a standard item in all testo 350 CO sensors. Flow and Mass Flow The testo 350 measuring system can determine flow, velocity, and mass flow by a variety of methods. A vane anemometer and hot bulb probe can be connected to the control unit for non-combustion flow measurements. However, typically in combustion sources, the differential pressure sensor and a pitot tube is the standard method. The Pitot tube can be exposed to the harsh environment in a stack. Input variable such as: pitot factor, stack diameter, absolute pressure, humidity and the analyzer will automatically calculate mass flow in lb/hr, ton/year, etc. Non-Heated Sample Line (testo Patented) (NO2/SO2-Hose) testo's non-heated sample line provides the sampling performance that is equivalent to a reference-level heated sample line. By incorporating: high velocity sample transport through a patented PTFE inner hose, minimized surface area, reduced residence time, and unique self-cleaning abilities, this technology eliminates the cost and bulk of heated sample lines. O2 Reference A concentration value that is reported in relation to a know reference. Regulatory authorities, engineering studies or other standard reporting may required a gas species (i.e. NOx or CO) to be reported to a specific O2 reference. This provides a method of comparing emission rates on an equivalent basis. For reporting, it eliminates the variability of having extra or deficient oxygen in a combustion system. Over – Range Protection The testo 350 has automatic sensor over-range protection. Whenever this limit is reached a fresh air rinse pump starts and purges the sensors with fresh air. The user can easily define the threshold for each sensor. 
Pellister (CxHy Sensor)A heated sensor that measures total hydrocarbons. Also know as a catalytic or heated bead sensor. It consists of specially matched pair of precision resistive thermal devices (RTDs) overlaid with two different coatings. The first one is covered with a propriety catalyst that creates an exothermic reaction to the presence of targeted hydrocarbons. The second RTD is covered with an inert coating and acts as a reference. Both RTDs are heated to approximately 950°F to increase the catalytic reaction rate. In the presence of hydrocarbons the catalytic RTD will have higher heat value than the reference. The RTDs are tried to two legs of a "Wheatstone Bridge" to maximize the output and stability. testo's unique cross calibration techniques essentially make the HC module blind to interference gases such as carbon monoxide and free hydrogen. The testo 350 is equipped with "Peltier" principle sample gas cooler (named after the French inventor Peltier). An electric current flows through the interface surface of two different metals thereby cooling one side and heating the other. The hot wet sample gas is exposed to the cold side element. This cooling process condenses the moisture thereby drying the sample. The testo 350 controls the current on the Peltier cooler to continually remove moisture from the stack gas. The condensed water is removed with a peristaltic pump and transported to the condensate trap. Pitot Tube A Pitot tube is a device that uses a two tubes that are configured to measure pressure thereby permitting the calculation for flow velocity. The testo 350 utilizes pressure sensors that measure the dynamic and static pressure through the Pitot tube configuration. By entering either manual or measured input parameters (i.e. temperature, humidity, pitot factor, etc.) flow velocity is automatically calculated. With the testo straight and standard "L" shaped Pitot tubes, nearly any application can be measured. Power / Battery / AC Operation The testo 350 Analyzer Box operates with AC line power (90-260VAC/50-60Hz) or through the "memory free" metal nickel hydride battery pack for up to 2.5 to 3 hours. Additional battery packs can be swapped out and connected as needed. (note: the batteries do not charge during AC operation) Sensor Upgrade Model An upgrade module is a measuring sensor that contains the original release information in order for the analyzer to measure a specific parameter. Once a module is installed in an analyzer it cannot be used again to upgrade additional analyzers, however, it can be used as a replacement or spare sensor. Note: A replacement sensor will not operate unless the original module (for that specific parameter) was install in that specific analyzer. testo-Databus A databus system is integrated into every testo 350 analyzer. It permits two-way communication (data transfer and function) through multiple devices (i.e. multiple analyzer boxes connected to analog output boxes connected to logger boxes, etc.). The maximum distances from end to finish is 3,000 feet. The testo-Databus can be used in 2 ways:
The testo 350 Analyzer Box has a socket that accepts a command (electrical signal) that will start a pre-configured automatic program. An external device can "trigger" the analyzer to start and stop sampling and monitoring (i.e. flip of a relay after exceeding a set limit). |
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