Pre-Quenching Corona Current Adjustment - Ricoh FT5540 Service Manual

31 August 1989

8.11 Pre-Quenching Corona Current Adjustment

Optimum Adjusting Value: DC + 17.0 + 2.0 µA
1. Disconnect the connector of the cleaning bias roller at the power pack as the on timing of
the cleaning bias roller and the pre-quenching corona are the same.
2. Reinstall the PQC unit, and position the drum shoe so that the axis of the current sensing
plate [A] is aligned with the PQC wire [B].
3. Select the dc 200 µA range on the digital rnultimeter.
4. To turn on the PQC, turn on the switching PCB dip switch corresponding to PQC on the
TC/SC power pack PCB. (The silk screen printed on the TC/SC power pack PCB is cor-
rect.)
5. Adjust the corona current by turning VR "PQC" [C] on the PQC/CB power pack. (Wait 30
seconds for the current to stabilize.)
6. Remove the drum shoe, and reassemble.
7. Check copy quality.
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