Paper Size Switches (Trays 2 and 3) The paper guides in Trays 2 and 3 operate four levers at the back of the trays that activate the size sensing switches (SW1601 through SW1604) mounted in the printer chassis. Paper sizes are compared to switch conditions in table 5-2. Table 5-2. Paper Size Switches Paper Size SW1601 SW1602 SW1603 SW1604 Ledger (portrait) OFF OFF OFF OFF A3 (portrait) OFF ON OFF OFF B4 (portrait) ON OFF OFF OFF Legal (portrait) ON ON OFF OFF Letter (landscape) OFF OFF OFF ON A4 (landscape) OFF OFF ON OFF Printing from Tray 1 The presence of paper in Tray 1 is detected by the Tray 1 Paper Present Sensor (PS1301).
The lifting plate pressurization solenoid (SL2) is then activated, releasing the plate that applies upward pressure on the paper and causing it to contact the Tray 1 pickup roller. The Tray 1 Feed Clutch (CL3) turns on at this time and feeds the paper from Tray 1 to the registration position. The remainder of the Tray 1 print process is identical to the Tray 2 and 3 process, described in “Printing from Trays 2 and 3” below. Printing from Trays 2 and 3 The Pickup, Feed, and Separation rollers start rotating when the DC Controller receives the /PRNT signal from the Formatter PCA.
Then, the DC Controller activates the Pickup Solenoid (SL1) and starts feeding paper through the Paper Input Unit (PIU), triggering photosensors PS2 and then PS1. These sensors inform the DC Controller that paper has passed through the PIU and is present at the Registration Assembly. When the Laser/Scanner and Fuser are ready, the DC Controller sends the /VSREQ signal to the Formatter. When the Formatter has processed the print data, it sends the /VSYNC and /VDO signals to the DC Controller. The paper is then released from the Registration Assembly (by CL1) and fed to the photosensitive drum, starting the C4085-91087 Paper Paths and Components 115