BFI Automation 2.0GT, Оригинальная инструкция по эксплуатации

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Description
5-1
5 Description
5.1 Functional description
The flame scanner 2.0GT operates on the basis of the
spectral analysis method of the UV-VIS and IR flame ra-
diation analysis. Both spectral ranges are converted sepa-
rately by a dual detector and are analysed selectively with
an automatic pre-amplifier and integrated frequency con-
troller.
The high-frequency flame modulation of the primary com-
bustion zone is utilised in an ideal manner in this way.
Cancellation of the UV-VIS flicker frequencies cannot oc-
cur again as the high-energy IR radiation is processed
separately. The usually undesired continuous-light part of
the flame is used for the fuel-specific control of the flame
scanner. A dual detector consists of a lead sulfide carrier,
to which a silicon photo element has been deposited by
evaporation. The Si element thus acts as an UV filter in
front of the PbS elements, which is located on the same
axis. Thus, the short-wave radiation part is blocked out
which otherwise could lead to problems in the use of PbS
detectors. The compensation controlled by the ambient
temperature stabilizes the operation point of the flame
scanner and maintain the spectral linearity. The signals of
both photo-elements results in an aggregate signal of a
every large spectral bandwidth in the mixed stage. Among
other things, the spectral shift of the flame renders infor-
mation on the oxidation of the fuel and thus on the quality
of combustion.
The signal parts of the UV-VIS and IR radiation intensities
can be set separately in order to exhaust the potentialities
of flame analysis to the full. The downstream bandpass
ensures that the typical flame radiation modulation of the
primary combustion zone only is used for the output sig-
nal. The other functional groups are used for conversion
into standardized digital information in the biggest possi-
ble interference safety.
The flame scanner has been fitted with an optical aper-
ture. The aperture permits a control of the radiation en-
ergy, which is picked up as flame signal by the semi-
conductor sensor. It is used to fade out excessive radia-
tion of heavy oil flames, for example, by optical means.
This prevents an overexcitation of the scanner electronics
or a thermal overload of the semi-conductor sensor.