Ricoh FT5233 Service Manual page 41

PROCESS CONTROL
When the drum initial setting (SP mode #66) is performed and more than 7
black copies are made, the initial V
copy job and the CPU stores the V
memory. ID sensor pattern detection and V
this initial V detection.
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ID sensor pattern and V
copies are made even in the SP mode. However, V
performed when a black copy is made in enlarge or full size mode and not in
the SP mode.
1.4.3 V Correction
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V Level (%)
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151~
101~150
0~100
The V sensor output is automatically adjusted to 4V (for Vlg=Vrg) by calling
SP mode #54 as we mentioned in 1.3.3 V
When the V pattern detection is performed during the operation, the CPU
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compares the Vdat with the Vref. According to the ratio between Vdat and
Vref, the CPU applies the voltage correction to the exposure lamp (V
Correction) as shown in the above table.
Vdat/Vref x 100 = V
The exposure lamp voltage for V
correction factors, and the new V
result is then applied to the exposure lamp voltage till the next V
detection.
detection is performed at the end of the
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reference value (initial Vlp/Vlg = Vref) in
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pattern detections are performed when black
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Lamp correction
voltage
–1 V
±0 V
+1 V
level (%)
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pattern detection depends on all previous
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correction factor is added to them. This
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2-12
pattern detection is done prior to
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pattern detection is
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Correction.
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12 February 1992
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pattern
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