Ricoh K-C3.5L Service Training page 63

Controlled by TD
and ID sensors.
There are four
modes but only
two can be used.
(See notes below
for details.)
Slide 63
There are four modes for controlling toner supply which can be changed with by SP
2921. The factory setting is SP2921 = 0.
Basically, the toner concentration in the developer is controlled using the standard TD
sensor voltage (Vts), toner supply reference voltage (Vref), actual TD sensor output
voltage (Vt), and ID sensor output data (Vsp/Vsg).
The Four Modes
• Sensor Mode 1: SP2921 = 0, Normal sensor control mode
• Sensor Mode 2: SP2921 = 1, Design use only (don't use)
• Fixed Mode 1: SP2921 = 2, Design use only (don't use)
• Fixed Mode 2: SP2921 = 3: Use temporarily if the TD sensor needs to be replaced.
Toner Density Control – 1
Overview
63
Toner Supply Motor
On Time Calculation
TD Sensor
Output (Vt)
Vt Reference
Voltage (Vref)
New Vref
Vt Reference
Voltage Update
Vref Update
ID Sensor Output
(Vsp/Vsg)
TD Sensor Initial
Setting (Vts)
Model K-C3.5L