Oki B 4100 Maintenance Manual page 526

2) Charging
Charging is affected by applying a DC voltage to the charge roller thta is in contact with the EP
(image) drum surface.
The charge roller is composed of two layers consisting of a conductive layer and a surface
protective layer that has elasticity, in order to secure a good contact with the EP (image) drum.
When the DC voltage (-1.35 KVDC) applied from the Power Supply Unit exceeds a threshold
value, charging begins. The applied voltage is proportional to charge potential with off set of
approx. -550V.
40055101TH Rev.4
PWU
EP drum
Charge Potential
[V]
-750
Charge roller
-550 -1350
Applied Voltage
[V]
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