REMS Drager FG7500 Betriebsanleitung Seite 62

Internal
Operating Instructions Dräger FG7500
7.4 Measuring combustion air temperature
If a separate combustion air sensor is not being used, the combustion air data must be
measured using the flue gas probe prior to the flue gas measurement. This menu item can
be skipped in the case of a flue gas measurement using a separate combustion air sensor.
7.4.1 Measurement with the flue gas probe
Start the combustion air measurement with "Combust. Air"
Insert the flue gas probe into the opening of the combustion air supply
intended for testing or optionally, hold the exhaust probe in the indoor
air.
As soon as the combustion air values have stabilized, press Hold. If
the combustion air supply has an oxygen-content below 21%, this can
be an indicator for a leak in the exhaust pipe in the air/exhaust system.
7.4.2 Measurement with the combustion air sensor
As an alternative, the combustion air temperature can be measured
during the flue gas measurement. To do so, the optionally available
combustion air sensor must be connected prior to the measurement
and positioned in the combustion airflow.
In this case, the combustion air temperature is accepted when determining the
measurement readings or during averaging.
7.5 Flue gas measurement
There are areas in the exhaust gas flow, which are only partially mixed
with exhaust. Therefore, it is necessary to obtain the sample from the
core stream. The core stream is distinguished by a maximum exhaust
temperature and a minimum oxygen concentration.
Start the flue gas measurement with "Flue gas".
Now, insert the flue gas probe into the exhaust pipe, move it in the
exhaust gas flow and position it, so that the tip of the probe is in the
core stream (highest gas temperature, lowest oxygen concentration).
In the process, you can use the yellow LED in the flue gas probe for
orientation. The LED lights up when the maximum exhaust
temperature has been reached; if you move the flue gas probe out of
the core stream, the LED starts blinking. After you have found the core
stream and the readings have stabilized, secure the flue gas probe in
this optimum position with the probe cone. A summary of the currently
measured combustion values is shown. Now, press the Hold button.
If you press the currently measured or calculated value, the display switches to the diagram.
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