Oce 3121 Technical & Service Manual page 673

If the DF is not used, the bin unit returns to the home position each time
Note:
a new document is positioned, and the copy button key is pressed. In this way,
no reverse sorting takes place.
If the copy count is set to '11' or higher (in excess of the count allowed
Note:
for the number of bins), a message will be indicated on the copier's control
panel to that effect.
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