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Measuring element | FWA 43xx / FWA 44xx | 29
Robert Bosch GmbH
1 690 326 006
2008-8-25
en
Camber LED
Fig. 37:
The Camber LED sends the light beam to the CCD
i
line of the same camera using a pendulum focus.
Camber pendulum with slit
Fig. 38:
Through the slit in the camber pendulum, the down
i
fall diode focuses its infra red beam on the CCD line.
Adjustment value
11.5.6
In order to achieve measuring accuracy, the camera
must be mechanically precise and electronically
adjusted.
There are possibilities of measuring differences
resulting from external mechanical influences, which
are to be corrected electronically using adjustment.
The adjustment program is integrated in user interface
and is menu driven.
The service technician and the user can adjust.
It is differentiated between two types of adjustment
values:
The correction values are determined only in plant
R
and permanently stored on an EPROM on camera
board.
The zero point values, in case of camera change and
R
annual maintenance as well as in case of servicing,
are locally determined by the service technician
with the menu driven adjustment program. The zero
point adjustment values are stored on an EPROM of
camera board and also stored permanently on the
measuring processor board.
Reading/ reflecting the adjustment values:
11.5.7
On every switch-on/reset of the MWA, a check sum
comparison is undertaken between the contents of
EPROMS of measuring processor and the camera.
If there are any differences, the adjustment values,
correction values and null point values of the camera
are reflected in measuring processor.
That means the memory of the camera is the master
memory for the adjustment value.
If there is any difference between the measuring
processor and camera memory, then in any case the
values from the camera are read and reflected in the
measuring processor.
Change camera
11.5.8
After changing the camera, the service technician must
carry out a zero point adjustment.
A calibre unit is required for zero point adjustment
(Adjustment bars). The process is supported by user
driven software.
see 14.6.
