BSI(Service Note) TOSHIBA
TOSHIBA TEC CORPORATION
2-4-1, Shibakoen, Minato-ku, TOKYO, 105-8524 JAPAN
BSI No
F99G734
SUBJECT
Change of High-Voltage Power Supply
MODEL
CATEGORY
Other countermeasures
From July 1999
CONTENT
Phenomenon/Cause
The HIC (Hybrid IC) may break when there is a electric leak or static electricity noise in the transfer
front guide bias output of the high-voltage power supply unit.
If the HIS breaks, the developer bias output becomes abnormal. As a result, the developer powder
scattering may occur.
DP2460, DP2570
FIELD APPLICATION
To be applied when necessary
FACTORY APPLICATION
Date
99/08/17
DTM-F9701, F9710
UNIT
Electrical Circuit
Countermeasure
As a countermeasure, insulating polyester film has been attached to the front guide and electric leak
has been cut as in BSI/F99G729 "Countermeasure to transfer guide electric-leak". In addition to the
above countermeasure, to protective the HIC against noise in this BSI, a condenser has been added
between the HIC power supply and the ground.
(Countermeasure parts)
As temporary countermeasure in which the condenser is attached to the current part will be applied
from July to September 1999. After September, the permanent part in which the pattern is changed
in respect to the added condenser is applied. The temporary part and the permanent one have same
part number (4408684000).
Identification by part
Before Change Temporary Countermeasure
(From July 1999)
Silk Printing
Color
Standard type NPKB695 NPKB695
White White Green
(Marked by fill dots at side of the
type name)
Permanent Countermeasure
(From Sept. 1999)
NPKB695B
Temporary Countermeasure (From July 1999)
BSI No. F99G734 Page 2
Identification mark for current
and new (fill dots)
Addition of condenser (0.22 µF)
[Changed/Added Part No.]
MODEL P-I Before Change After Change Note P I R FAA
DP2460
DP2570
P-I: Page-Item P: Contents of Change I: Interchangeability R: Reasons for Change
7-31 4408683860
PS-HVT-220
4408684000
PS-HVT-220
C B D Y