50 SERVICE Error - Fuser Malfunction

W a r n i n g The Fuser Assembly is HOT. Allow the assembly time to cool before servicing.

The purpose of the fusing system is to maintain a constant temperature on the fuser roller. A high intensity fusing lamp, located inside the fuser roller, provides the high temperature required for the fusing process. While the printer is in standby mode, a temperature of approximately 172° C is maintained on the fuser roller. While the printer is in printing mode, a temperature of around 183° C is maintained.

The main components of the Fuser Assembly are the fusing lamp and its associated fusing and pressure rollers, a thermistor, thermoprotector, and the AC controller/safety circuitry in the AC Power Supply. The fusing lamp is a specially designed 460 watt (220V), or 500 watt (115V) halogen lamp that operates at line voltage. The thermistor is a resistor whose value changes with temperature. At room temperature the resistance value of the thermistor should be between 180k ohms and 280k ohms.The thermoprotector is a switch designed for over-temperature protection, and opens when the temperature reaches 230° C. The thermoprotector will not reset when the fuser cools. It may be necessary to replace the thermoprotector or fuser assembly if the thermoprotector opens.

The following conditions result in a fusing error:

1 Unable to maintain a temperature above approximately

180° C.

2 A temperature above 230° C.

3 A condition wherein a temperature of 165° C is NOT reached within 90 seconds after power-up.

N o t e

If a 50 SERVICE error message is displayed, turn

 

the printer OFF for at least 10 minutes. Failure

 

to wait the full 10 minutes before turning the

 

printer ON results in a continuation of the error

 

message and the shutting off of the fuser lamp

 

current during this time, though the source of the

 

error may have already been resolved.

Troubleshooting 7-29