Initializing the upper document feed roller When the separation roller starts to rotate, the position of the upper document feed roller is simultaneously initialized to raise the document stopper. Initialization is carried out when the power is turned ON, when documents are inserted and when documents are ejected. Document feed lever Switching between automatic document feed and manual document feed is carried out by the document feed lever above the left side of the LCD. During automatic document feed, documents are gripped between the separation guide and the separation roller. Switching the lever to manual document feed raises the separation guide and frees it from the document. Manual document feed can therefore minimize the possibility of damage caused by pinching between the separation guide and separation roller when feeding documents such as thickstock paper or photographs. However, because document separation does not occur in manual document feed mode, only one sheet at a time may be loaded. Loading multiple sheets will result in double feed. Document Jam Detection There are two types of document jams which may occur: a) Feed jam Occurs when the document edge sensor cannot detect the document's leading edge within 15 seconds after the start of document separation. b) Eject jam/document too long Occurs when the document edge sensor cannot detect the document's trailing edge within one meter of feeding after the document's leading edge is detected. When one of these types of jams occurs, all data which have been read and stored in memory (except pages that have already been completely transmitted or copied) are erased.