Ricoh Aficio 1013 Service Manual page 175

DEVELOPMENT
6.12.2 DEVELOPMENT BIAS
[A]
[B]
B046D309.WMF
Black areas of the latent image on the drum are at low negative charge (about
-140 ± 50 V), with white areas at high negative charge (about –900 V).
To attract negatively charged toner to black areas, the high voltage supply board
[A] applies a (default) bias of –600 V to the development roller [B]. The bias
voltage can be adjusted with SP2-201-1.
SM 6-33 B044/B045/B046