Cpm Down For Thick Paper; Overheat Protection - Ricoh B291 Service Manual

6.15.10 CPM DOWN FOR THICK PAPER

When printing on thick paper the machine automatically controls and lowers the
line speed to below 45 ppm to ensure sufficient heat to fuse the toner to the thicker
paper.
• After switching from Normal to Thick Paper for printing, the machine halts
temporarily and re-starts for 35 cpm running.
• If the previous job included stapling or other finisher processing, these settings
remain in effect for the next job on thick paper after the line speed is adjusted.
• If the print job on thick paper does not include an image on the page (a cover),
then the speed is not adjusted down from 45 cpm to 35 cpm.
NOTE: The previous machine automatically reduced line speed 30% (ppm
down) for thick paper. In these models, however, the speed is reduced
from 45 cpm to 35 cpm for the 45 cpm machine. This adjustment is
performed automatically for the B295/B297 (45 cpm) machine only.
Note these other important points regarding cpm down for thick paper on the 45
cpm machine:
• When the line speed switches from 45 cpm to 35 cpm for thick paper, the
transfer current changes to the settings specified with SP2301 (Transfer Current
Adjustment). (For details, see Section "5. Service Tables".) Bias voltage,
development and other settings are not affected.
• Fusing temperature adjustment switches on, but no operation can start until the
machine reaches the temperature specified for the job.
• The ID sensor pattern is created and the line speed remains the same until the
end of the job.
• The intensity of the LD unit is lowered evenly, 30 steps from its specified value.

6.15.11 OVERHEAT PROTECTION

If the hot roller temperature becomes greater than 250°C, the CPU cuts off the
power to the fusing lamp, and SC543 (Fusing Overheat Error) will be displayed.
Even if the thermistor overheat protection fails, there is a thermostat in series with
the common ground line of the fusing lamp. If the temperature of the thermostat
reaches 199°C, the thermostat opens, removing power from the fusing lamp. At the
same time, the copier stops operating. At this time, SC542 (Fusing Temperature
Warm-up Error) will be displayed.
SM
CÓPIA NÃO CONTROLADA
6-101
CÓPIA NÃO CONTROLADA
IMAGE FUSING AND PAPER EXIT
B291/B295/B296/B297