Overheat Protection - Ricoh B245-62 Service Training

Fusing Overheat Error 1
If the fusing temperature reaches more than 230°C and
continues 10 times consecutively (100 ms x 10 = 1 second),
SC543 shows on the LCD and the controller turns the
fusing lamp off.
Fusing Overheat Error 2
If the fusing temperature reaches more than 250°C and
continues 10 times consecutively (100 ms x 10 = 1 second),
SC544 shows on the LCD and the controller turns the
fusing lamp off.
Overheat Fail-safe
The two thermostats provide overheat fail-safe protection.
They are on the line of the fusing lamp. They cut the power
supply to the fusing lamp if the temperature of the
thermostats reaches 180°C.
Slide 107
Fusing overheat error 1 is detected by the thermistor.
Fusing overheat error 2 is detected by the fusing temperature control circuit.
The thermostats are near the hot roller but not in contact.

Overheat Protection

107
B245-62 / PD-C4