Low Image Coverage - Ricoh G104 Service Manual

4. Hybrid control mode
This is the default toner supply control mode. The TD sensor or the pixel count
are used in this mode.
• If the image coverage ratio is less than the value of SP 3-701-002 to 005,
pixel count is used.
• If the image coverage ratio is more than the value of SP 3-701-002 to 005,
the TD sensor is used.
• But, if SP 3-701-001 is 'off', then the TD sensor is always used. The default
setting for this SP is 'off'. Because of this, pixel count is not used.
The amount of toner supply can be adjusted with SP3-306-009 to -020.
The TD sensor is in the PCU. If the TD sensor becomes defective, the
technician must replace the PCU. But if this is not possible at that time, the
technician can change the toner supply mode with SP 3-301-001 to 004.

Low Image Coverage

After process control, toner refresh mode is done (this can be switched off with SP
3721 001).
• Toner refresh is only done if the percentage of pages (after the previous process
control) that was detected with low image coverage is more than the value of SP
3721 002.
• SP 3701 002 to 005 control the limits that the machine uses to detect if the
image coverage is low.
Toner refresh mode supplies new toner, because there is old toner in the developer
after printing many pages with low image coverage.
During toner refresh mode, the machine does the following:
1) The machine mixes the developer for 5 seconds.
2) The machine does an engine free run, which simulates printing of 10 sheets
of A4/LT size paper with the image data (2 by 2) and normal toner supply.
3) The machine mixes the developer for 10 seconds.
SM
CÓPIA NÃO CONTROLADA
6-13
CÓPIA NÃO CONTROLADA
PROCESS CONTROL
G104