Toner Density Control - Ricoh Neptune-P1 Service Manual

6. Details
• If the machine detects Vsg > 2.5 V, it will perform adjustments or issue SC401 as shown below, based
on the value of the Vsg reading.
ID Sensor Recalibration
Readings (V)
Vsg < 3.9
Vsg = 3.9 to 4.10
Vsg = 4.1 to 4.2
Vsg = 4.2 to 4.5
Vsg = 4.5 to 4.8
Vsg > 4.8
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• If SP2804 is set to clean the charge corona wire during warm-up, Vsp/Vsg is measured after the wire
is cleaned.
• The machine measures Vsg after the machine is powered on or returns from the low power mode, if
SP2924 is set to "0" or "1". (The default is "0", which means that the machine measures Vsg after
power on when the fusing temperature is below 50
• If the machine is switched off and on after the warm-up sequence when Vsg is less than 2.5V, the
warm-up sequence is done, and the setting of SP2924 (Warm-up Control) is ignored.

Toner Density Control

Overview
This machine uses an ID sensor to control:
• Toner density
• Toner near end detection
• Toner end detection
The machine uses the ratio of Vsg/Vsp to find the quantity of toner that must be supplied to the drum.
To supply toner, the machine switches on the toner supply clutch to feed toner from the toner cartridge to
the development unit.
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How the ID Sensor is Recalibrated
PWM value +0.5%
ID sensor is re-calibrated automatically with the stored PWM value.
PWM value -0.2%
PWM value -0.5%
PWM value -1.0%
SC401 occurs (ID Sensor Vsg Error). For more see Section "4. SC
Code Descriptions".
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C.) For more, refer to "Service Tables".