TM 5-6675-324-14
(d) High-voltage power supplies. The high-voltage transformer provides
high voltages to various corona units and the developing assembly, as commanded by
microcomputer Q203. There are two power supplies for the high-voltage transformer:
an unregulated 24 V dc to HVT1-1 for primary, secondary, transfer, and precondi-
tioning coronas (U24 V dc) and a regulated 24 V dc input to HVT1-7 for developing unit
bias. When Q203-22 outputs RMH1, the input to HVT-1-7 = O and primary, secondary,
transfer, and preconditioning coronas are enabled. At the same time, Q401 turns on
to provide 24 V dc to HVT1-7, which provides developing unit bias. When DRMD = 1
from Q203-24, HVT1-5 = O and secondary corona voltage is high (-6.5 kV). When RMH2L
= 1, the voltage is low (-5.5 kV).
HIGH-VOLTAGE OUTPUT
-5.1 kV
Preconditioning
+6.3 kV
Primary
-6.5 kV (High Output)
Secondary
-5.5 kV (Low Output)
+6.3 kV
Transfer
1 kV ac P-P, 0.4 kHz
Developing Bias
3-30