Gestetner G060 Service Manual page 245

6.2.5 TONER NEAR END/TONER END DETECTION
Introduction
The machine is always checking for a toner near end condition.
Toner Near End Detection
When the following condition is detected for a toner color during a print job, the
machine automatically stops the print job and performs toner end recovery. If the
result of toner end recovery does not meet the condition described in Toner End
Recovery below, the machine flags a "toner near end condition".
• V
+ 0.4 V < V
REF
Toner End Detection
The machine flags a "toner end condition" when one of the following conditions are
detected for a toner color.
• V
+ 0.8 V < V
REF
• The pixel counter counts up the equivalent of 5 A4 sheets of pixels (100%
coverage) since near-end was detected.
However, if fewer pages have been made since near-end than the number
guaranteed with SP 2-212-11 (default: 10 pages), printing will continue.
NOTE: If one of the following conditions are detected 10 consecutive times, the
machine flags a "toner end condition" regardless of the number of pages
printed since near-end.
• V
+ 1.2 V < V
REF
• V
> 4.8 V
T
After the machine detects toner end for black, it cannot print until the toner
cartridge is replaced. If toner end is detected for cyan, magenta or yellow, the
machine can print with black and white only; color printing is disabled.
Toner End Recovery
The machine detects that the toner cartridge has been replaced if the upper right
cover is opened and closed when a near-end or end condition exists. The machine
then starts to supply toner to the development unit. After supplying toner, the
machine clears the toner end condition if the following conditions are detected.
• Vt [0] – Vt [3] > 0.5V
• Vt – Vref > 0.3V
SM
(ten times consecutively)
T
(ten times consecutively)
T
T
6-15
PROCESS CONTROL
G060