Ricoh B286, Service Manual, Page: 582 / 622

Fusing Unit
B286/B289 6-74 SM
Note :
If the target pressure roller temperature is set for 65°C, inching with rotation of the pressure
roller and hot roller starts, then the copy ready temperature is set when both temperatures
at and are reached.
! Inching Start Temperature = SP1937-3
! Pressure roller target temperature for inching control: SP1948
Fusing Temperature Control: Temperature Feedback During Copying
This machine uses the feedback of the hot roller thermistor and two pressure roller
thermistors, one at the center and one at the end of the pressure roller, to control the fusing
temperature. The SP codes settings shown in the tables and illustrations below determine
how fusing temperature is controlled for the paper thickness modes (Mode 1 to 5) for each
type of paper.
Here is a quick summary of the SP codes that are used to maintain optimum fusing
temperature.
!
These SP codes are set at the factory and normally should not require adjustment
in the field.
1931 Target Temp: Hot Roller Sets the target temperature of the hot roller.
1932 Target Temp: Press Roller
Sets the target temperature of the pressure
roller
1934 Lower Limit Temp: Hot Roller
Sets the minimum difference in temperature
allowed between the actual temperature and
the target temperature of the hot roller
1935 Pressure FB Control Steps
Changes the stepped adjustments of SP1932
(Target Temp: Pressure Roller) by using the
sum of the settings of SP1932 (Target Temp:
Pressure Roller) +SP1935 (Press FB Control
Steps).
1941
Press FB Ctrl Switch by Temp
Diff
Sets the temperature differential that
determines when the machine switches to the
supplement mode for pressure roller feedback
control. (See description below.)