Specifications

6.5 ABNORMAL CONDITION IN TONER DENSITY
DETECTION
If the Vsg goes below 2.5 volts (Vsg abnormal) or Vsp goes above 2.5 volts
(Vsp abnormal) 5 times in a row, the CPU determines that toner density
detection is abnormal. The CPU changes from the detect supply mode to the
fixed supply mode. At the same time either the Auto ID indicator or the
selected manual ID level starts blinking, and the machine can be operated.
Abnormal Condition In Toner Density Detection
SP mode #55 Display
Conditions
Vsp Vsg
varies 0.00
Vsg ≤ 2.5 (Vsg Abnormal)
varies 5.00
Vsp ≥ 2.5 (Vsp Abnormal)
6.6 DEVELOPMENT BIAS FOR ID SENSOR
The development bias for the ID sensor consists of the following 2 factors:
Development bias voltage = Toner density adjustment factor
+
Vd correction factor
The development voltage for the Vr correction is 0 volts.
6.6.1 Toner Density Adjustment Factor
Toner Density Adjustment
(Black Toner: SP Mode #33, Color Toner: SP Mode #75)
Toner Density
SP Data
(SP mode
#33 or #75)
Development Bias Voltage
Black Toner Red Toner Blue Toner Green Toner
Normal 0 –260 volts –240 volts –300 volts –320 volts
Low 1 –220 volts –200 volts –260 volts –280 volts
High 2 –280 volts –260 volts –320 volts –340 volts
Higher 3 –300 volts –280 volts –340 volts –360 volts
Developer Initial Setting –340 volts –280 volts –240 volts –240 volts
The development bias can be adjusted by SP mode #33 for black toner or
#75 for color toner to adjust the toner density level. The above chart shows
the development bias voltage corresponding to setting of SP #33 or #75. This
adjustment should be used only when the exposure lamp voltage adjustment
(SP mode #48) can not achieve the desired image density.
1 December 1990
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