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5. Controlling the DC Component of the Separation/Pre-Transfer Corona Current
If an overcurrent flows into the separation/pre-transfer charging assembly, the high-
voltage stop signal (HVTOFF) is generated to temporarily stop the corona current
(DC/AC component) applied to the pre-transfer/separation charging assembly.
When HVOFF is generated, the copier continues to operate, and the application of
the corona current will be resumed when the application current returns to normal.
If leakage occurs because of an overcurrent caused by a broken charging wire or the
like, and HVTOFF continues as a result, the application will not be resumed unless the
cause is removed.
When the corona current applied to the transfer/separation charging assembly
stops because of an overcurrent, separation jams tend to occur frequently.
Since the control panel will not indicate any message, check the relevant
mechanisms if separation jams are frequent.
*Output from the DC controller PCB (connector of signal name).
Table 4-104 Combinations of Transfer/Separation Signals
COPYRIGHT © 1997 CANON INC. CANON NP6350/NP6251 REV. 0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 4 IMAGE FORMATION SYSTEM
4-18
Switching signals
Control signals
Signal*
DCON
HVT.POST.AC
ACBTP
ROED
HVSTC
HVT.POST.DC
HVT output
J114A-10
J114A-7
J114A-3
J114A-1
J114A-8
J114A-9
Pre-transfer ON
‘1’
‘1’
‘1’
‘0’
—
3~11V
Pre-transfer OFF
‘0’
‘0’
‘0’
‘0’
—
2V
Separation ON
‘1’
‘1’
‘1’
‘0’
3~11V
—
Separation OFF
‘0’
‘0’
‘0’
‘0’
2V
—