BFI Automation 2.0GT, Original Operating Instructions

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Technical data
3-4
3.5.2 Optical aperture
The flame scanner, type 2.0GT, has been fitted with an
optical aperture. The aperture permits a control of the ra-
diation energy, which is picked up as flame signal by the
semi-conductor sensor. It is used to fade out excessive
radiation emitted by heavy oil flames, for example, by op-
tical means. An overexcitation of the scanner electronics
or a thermal overload of the scanners can be prevented.
Adjustment of the aperture
The unit has to be opened for the adjustment of the aper-
ture (four cross-recessed screws on the lens plate below
the sponge rubber disk). The aperture is located between
the lens and the detector holding block. In order to be
able to change the aperture setting, the rotational axis
screw (1) has to be loosened first of all. Then loosen the
set screw (2) until the aperture can be moved. Set the re-
quested aperture (3-5) and lock the position with the set
screw (2). Subsequently tighten the rotational axis screw
(1) and close the device.
1 rotational axis
2 set screw
3 small aperture
4 medium aperture
5 big aperture