Lexmark Optra Color 1200 Service Manual page 37

5050-001
Belt Up or Down (BUD)
During monochrome printing, only the black transfer and
development functions operate. An electromagnetic clutch in drive 1
operates to pull the transfer belt down as the paper passes under
the color PC drums. A cam on the changing shaft moves the belt up
and down through gears from the belt unit drive motor on the unit
frame.
The position of the belt is detected by a photo sensor from the cam
position.
General Information
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