Ricoh G148, Service Manual

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Any SC codes that are generated during auto process control are logged in the memory and do not appear.
The machine will continue to operate.
Drum Potential Sensor Calibration
The potential sensor output is affected by the distance of the sensor from the OPC, paper dust or other
matter on the surface of the sensor, and environmental conditions. For these reasons, the potential sensor
is calibrated often, as described below.
1. 100 samples are taken at –100V and at –800V, and the readings are averaged.
2. If the readings are within the normal range, then these readings are used to calibrate the potential
sensor.
If the variations in the readings exceed the specified range, then an SC is logged (Sensor Calibration
Error, SC310 to SC317) and automatic process control halts. The charge grid voltage Vg, develop-
ment bias, and LD power are set as follows.
• Development bias is set to the value stored in SP2201-001
• Grid voltage is set to the value stored in SP2001-001
• Laser power is set to a fixed value
Development Bias, Bias Grid, and LD Adjustment
Development Bias (Vb)
First, the development bias that will be used for copying (Vb) is determined by measuring the potential of
a pattern made on the drum using a fixed grid voltage, development bias, and laser power.
6. Details
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