Ricoh Aficio 2022, Service Manual

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DRUM CHARGE
B089/B093 2-30 SM
If the humidity drops, the drum potential goes up (to a higher –ve voltage) even if
the charge roller voltage supply stays the same (efficiency of voltage transfer is
higher with lower humidity). As a result, less toner is transferred to ID sensor
pattern [B]. If the sensor output reaches a certain point, the drum charge voltage
will be reduced.
To determine whether to change the drum charge roller voltage, the machine
compares Vsdp with Vsg.
•
Vsdp / Vsg > 0.95 = Reduce the magnitude of the drum charge voltage by 50 V
•
Vsdp / Vsg < 0.90 = Increase the magnitude of the drum charge voltage by 50 V
2.6.2 ID SENSOR PATTERN PRODUCTION TIMING
The ID sensor pattern is made in the following conditions:
• During warming up at power on
•
If the machine starts warming up after a certain time (default: 30 minutes) has
passed since entering night mode or low power mode
The 30-minute interval can be changed using SP2995-1.
•
At the end of a job, if an ID sensor pattern has not been made for a certain
number of sheets (default: 0 sheets = disabled)
The number of sheets can be changed using SP2995-2.