Lexmark Optra C710 Service Manual - Page 52

5016-001 Detecting New Cleaning Unit Detecting the cleaning unit in the Fuser Assembly A thermal fuse is attached on the contact point A in the cleaner unit. When the cleaner unit is placed inside the fuser unit, contact A contacts contact B. The circuit is then complete through the thermal fuse. When primary power is applied to the printer, a current flows through the thermal fuse detecting a new cleaner unit and the print counter resets to 'Zero.' As the temperature of the hot roll and cleaning roll rise, the temperature around the thermal fuse also rises, eventually causing the thermal fuse to blow. Note: The fuse will generally blow after primary power has been applied following the printing of two or three sheets of paper. At this time the temperatures of the blown fuse and surrounding parts are 70 degrees C and about 100 degrees respectively. When predetermined sheets of paper are printed, a warning displays. When additional sheets are printed, the printer stops until the unit is replaced. When a new unit is placed, repeat the previous step. 1-28 Service Manual