Various Control Mechanisms; Fixing Temperature Control; Protective Functions - Canon M3010 Series Service Manual

2
Technical Overview > Fixing System > Various Control Mechanisms > Protective Functions

Various Control Mechanisms

■ Fixing Temperature Control

● Heater Temperature Control
The heater temperature control is to keep the fixing heater in the fixing film unit to the
specified temperature.
The engine controller monitors the Fixing Heater (H1) temperature detection signal (FSRTH)
and outputs the fixing heater drive signal (FSRD) according to the detected temperature.
The fixing heater drive PCB controls the Fixing Heater (H1) according to this signal to keep
the fixing heater temperature within the target values.
Engine controller
Low-voltage
power supply
CPU
Frequency
FREQSNS
detection
circuit
(220-240V model only)
FSRD
RLYD (24VOFF)
FSRTH
Fixing heater (H1)
Thermistor (TH1)
Pressure
roller
Fixing film
Thermal fuse (TP1)
2 Technical Overview > Fixing System > Various Control Mechanisms > Protective Functions
Fixing control
Relay drive
FU101
circuit
RL101
Fixing heater
safety circuit
Fixing heater
drive circuit
Fixing target temperature varies according to the fixing mode, and there are 8 types of the
mode.
These modes are determined according to the paper type settings and resolution settings (see
the caution) in a driver.
The following table shows the relationship between the fixing target temperature and the
settings (paper type settings and resolution settings) in a driver.
Paper type settings Vertical scanning
Plain paper
Plain paper L
Heavy paper
Heavy paper H
Transparency
+24V
Postcard/postcard H
Envelope
Labels
CAUTION: Resolution switching
The machine provides two types of resolution: 600 x 600 dpi and 600 x 400 dpi.
The selection is made by the "Copy Type" setting in the printer driver.
For speed priority (at the time of shipment), 600 x 400 dpi is selected, but changing to
resolution priority selects 600 x 600 dpi.

■ Protective Functions

● Protective Function of fixing assembly
Host machine carries the following 3 functions to prevent the Fixing Heater (H1) from
overheating.
1) Protective function by CPU
F-2-23
CPU of engine controller monitors the Thermistor (TH1) temperature consistently.
When Thermistor (TH1) reaches approx 220 deg C, CPU determines that the Fixing Heater
(H1) is overheating and stops the fixing heater drive signal (FSRD) output and also turns
OFF relays to shut the power supply to Fixing Heater (H1).
Printer driver settings Fixing target
temperature
600 dpi 155 to 165 deg C
400 dpi 170 to 190 deg C
600 dpi 145 to 155 deg C
400 dpi 160 to 180 deg C
600 dpi 170 deg C
600 dpi 185 deg C
600 dpi 150 to 160 deg C
400 dpi 165 to 180 deg C
600 dpi 188 deg C
400 dpi 188 deg C
600 dpi 160 to 165 deg C
600 dpi 170 deg C
2-20
T-2-5
2-20