Panasonic FP-7818, Service Manual & Parts Manual

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(5) Temperature control
The heat roller is provided with two halogen lamps (main heater lamp and sub
heater lamp). The main heater lamp turns ON during warming up and copying
operation.
To control the maximum power consumption, the sub heater lamp turns ON
during warming up and after release of pre-heat mode only in order to reduce
the warming up time of fuser unit.
The temperature control in the copying operation and the standby is done by
the main heater lamp.
• Sequence
a) When turning ON the power, the main heater lamp and the sub heater lamp
turns ON, which heats the heat roller.
b) At a specified temperature, the main motor turns on and the heat roller and
the pressure roller rotate. After all copy quality standards are set, the main
motor turns off. When the heat roller temperature reaches the specified value,
the machine is ready.
c) Afterwards, the thermister detects the temperature of heat roller. The heat
roller keeps the temperature to the specified value by turning on/off the main
heater lamp.
(Note)
• When the temperature of heat roller surface does not reach the specified value
in the specified time from power ON, the error E4-01 is indicated.
• If when the power is turn ON in an absolutely frozen condition of fuser roller (a
very cold morning) or copies are continuously made, the operation of main
heater lamp is inadequate. In this case, the number of copies per min. will be
reduced (no change for process rate)to increase fusing time.
When the temperature of the heat roller surface rises enough, the machine
speed will return to the regular number of copies per min.
(°C)
190
ON
Switch
Print key Energy
Saver ON
Energy
Saver OFF
Copy
complete
Warm-up
complete
Heat roller surface temperature
ON
0
175
Time
210 sec.
Main motor
Main lamp
Sub lamp