Theory of Operation Ver. 8.0 Jun. 2008
19. Fusing section
14
3
2
Composition/Operation
19.3.11
PPM control
• PPM (PCM) control is made to secure the paper space and reduce the number of print-
ing per minutes so that the center temperature of the heating roller and pressure roller
can be reduced, which prevents the edge temperature from going up.
• With this PPM control, the productivity is decreased by between 40 to 90% compared
with the normal mode.
• Select the correction rate by three judgment steps, make the PPM control in minimum
rate.
Ex: In case the 1st judgment: 70%, 2nd judgment: 60%, 3rd judgment: 100%, it will con-
trol with 60% correction rate.
• PPM control makes the judgment in every given period to print with the corrected PPM
control
Ex: In case the printing of 55 sheets/minute with 60% correction rate, it will be 33 sheets/
minute.
• The speed is adjusted (up/down) by 10% in every given period.
Example:
MF
550 PPM control
2
2
Judge-
ment
Measurement
time
Criteria
Corrected
rate
1
5 seconds
after print
starts
Low temperature mode when print starts and the temperature
inside the unit is 18 degrees centigrade or below
70%
Other than above
100%
2
60 seconds
after print start
Low temperature mode when print starts and the temperature
inside the unit is 18 degrees centigrade or below
70%
Other than
above
Central temperature of the heating roller is lower
than setting value by up to 15 degrees centigrade
Central temperature of the fusing pressure roller is
lower than setting value by up to 35 degrees centi-
grade
100%
Central temperature of the heating roller is lower
than setting value by between 15 to 25 degrees
centigrade
Central temperature of the fusing pressure roller is
lower than setting value by up to 5 degrees centi-
grade
80%
Central temperature of the heating roller is lower
than setting value by over 25 degrees centigrade
Central temperature of the fusing pressure roller is
lower than setting value by up to 5 degrees centi-
grade
70%
Central temperature of the heating roller is lower
than setting value by between 15 to 25 degrees
centigrade
Central temperature of the fusing pressure roller is
lower than setting value by between 5 to 35
degrees centigrade
70%
Central temperature of the heating roller is lower
than setting value by over 25 degrees centigrade
Central temperature of the fusing pressure roller is
lower than setting value by between 5 to 35
degrees centigrade
60%
Y107522-3 Theory of Operation
