Bias Compensation Factors; Rest Time Compensation (V2) - Ricoh FT4430 Service Manual

3. Bias Compensation
As discussed previously, either the automatic image density system or the
operator, through the image density keys, sets the bias base level (V1). The
CPU increases the bias base level as necessary to compensate for the rest
time between copy runs and the drum temperature, both of which affect drum

4. Rest Time Compensation (V2)

The drum sensitivity often drops slightly over the first few cycles of a copy
run. This is because the light from the exposure lamp fatigues the drum
slightly, and it takes
that the sensitivity drops depends on the drum's temperature and the rest
time between copy runs (the longer the rest time, the greater the change).
The copier increases the bias at the beginning of each copy run to prevent
variations in the image density of the first few copies produced. The above
two tables show the amount of bias increase. If the drum temperature is less
than 10 degrees Celsius, no rest time compensation is applied.
When the main switch is turned on, the CPU automatically selects the "greater
than two hours" rest time compensation level.
Factors
T D : D r u m T e m p e r a t u r e
a
few copies for the selenium to restabilize. The amount
2-29
16 April '88
.