Toner End Detection - Ricoh B202 Service Manual

PROCESS CONTROL

Toner End Detection

The machine flags the toner end status when one of the conditions below is
detected for a toner color. The messages, "No Toner," "Replace Toner Cartridge,"
and "Xxxxx," show. "Xxxxx" indicates the color, such as cyan.
• V
+ 0.5 V < V
REF
• The pixel counter counts up to the equivalent of 50 A4 sheets of pixels (100%
coverage) since near-end was detected.
However, printing continues if fewer pages have been made since near-end than
the number set with SP 2-212-11 (default: 10 pages).
NOTE: If one of the following conditions is detected 10 consecutive times, the
machine flags a "toner end condition". This condition does not depend on
the number of pages printed since near-end.
• V
+ 1.2 V < V
REF
• V
> 4.8 V
T
The machine cannot print until the toner cartridge is replaced after it detects toner
end for black. The machine can print in black and white only if cyan, magenta, or
yellow are in a toner end condition during standby mode. At this time the machine
cannot do color print jobs.
NOTE: If the yellow, cyan, or magenta toner ends during a color-printing job, the
job is suspended until toner is supplied. If new color toner is not installed,
the user can print black-and-white jobs only.
Toner End Recovery
The machine assumes that the toner cartridge has been replaced if either of the
following occurs when the near-end or end status exists:
• The upper right cover is opened and closed.
• The main switch is turned off and on.
Then the machine starts to supply toner to the development unit. After supplying
toner, the machine clears the toner near-end or end status if the following
conditions are detected:
• Vt [0] – Vt [3] > 0.5V
• Vt – Vref > 0.3V
B202/B178/B180
(ten times consecutively)
T
T
6-18 SM