ADF document size detection The sensors and the potentiometer send signals to the SCB, and these signals are transferred through the intermediate PCB to the CPB. The CPB calculates the size of the document based on the signals in the service menu. ADF document size detection terminology TRS-S: ADF document length detection (short) TRL-S: ADF document length detection (long) TRVR: ADF width detection unit (potentiometer) Note The width detection unit can be calibrated in the service menu. Figure 56. ADF document size detection 90 Chapter 5 Theory of operation C8523-90921