When the Vsp/Vsg x 100 becomes greater than 28.0 for two consecutive toner detection cycles, the CPU determines immediately that there is a toner end condition and copying is inhibited. This causes the Add Toner indicator to light and the Start indicator turns red. Example: (Detect Mode)
Copy number 1st�5th copies 6th�10th copies 11th copy Toner density detection cycle 1st copy 6th copy 11th copy Vsp/Vsg x 100 18.3 28.3 28.3 Toner supply ratio (If SP31=0) 30% 60% � Add Toner indicator lights. (Toner end condition) Indicator
6.7.3 Toner End Recovery After the toner cartridge is replaced and the front cover is closed, the CPU turns on the main motor, and turns on the toner supply clutch to supply toner to the development unit from the toner cartridge. Toner density is detected (Vsp and Vsg are monitored) during this period. When Vsp/Vsg x 100 becomes less than 15.2, the main motor is turned off and the toner end or near end condition is cleared. If Vsp/Vsg x 100 stays greater than 15.2 (when the toner cartridge is not replaced), the toner end or near end condition is not cleared. If Vsp/Vsg x100 stays between 15.2 to 28.0, only one copy can be made. After the copy job the Add Toner indicator lights and copying is inhibited. If Vsp/Vsg x100 stays grater than 28.0, copying is inhibited. This prevents the customer from making copies with the toner end condition by opening and closing the front cover.