Drum Potential Sensor Calibration - Gestetner B070 Service Manual

Drum Potential Sensor Calibration

The drum 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 –200V and at –700V, and the readings are averaged.
Applied Bias
0V
-200V
2. If the readings are within the normal range, then these readings are used to
calibrate the drum potential sensor.
If the variations in the readings exceed the specified range, then an SC is
logged (Sensor Calibration Error, SC310 to SC312) and automatic process
control halts. The charge grid voltage Vg, development bias, and LD power are
set as follows.
• Development bias is set to the value stored in SP2201 1
• Grid voltage is set to the value stored in SP2001 1
• Laser power is set to the values stored in SP2103
SM
CÓPIA NÃO CONTROLADA
-700V
Sampling
500 ms 100 rev.
100 ms intervals
6-67
CÓPIA NÃO CONTROLADA
DRUM UNIT
Sampling
500 ms 100 rev.
100 ms intervals
B070D997.WMF
B070/B071