Toshiba e-STUDIO520 Service Manual page 298

Relation between IH status signal and IH errors (L: Low level, H: High level)
Checking
timing
IHERR1
Front cover L
(upper) is
closed at
power ON
On usual
L
L
L
H
H
H
H
Front cover L
(upper) is
opened
e-STUDIO520/600/720/850 FUSER UNIT
Signal
IHERR2 IHERR3
L
L
H
H
L
H
H
H
L
(Other than the above)
Status
L Abnormality detected at
initialization
* An abnormal status is
detected at the initial-
ization.
Power voltage abnormal-
ity
* AC power is not sup-
plied to the IH board.
H Power voltage upper limit
abnormality (Surge detec-
tion)
* AC input voltage has
exceeded 122% of the
rated voltage
L Switching element (IGBT)
abnormality
* Wire breakings, short-
circuits abnormal fluc-
tuations or overheating
(= insufficient cooling)
of IGBT
H IH abnormality
L No abnormality
H Power voltage lower limit
detection (not error)
* AC input voltage has
dropped to less than
85% of rated voltage
L Input current lower limit
abnormality
* Wire breakings or
improper installation of
IH coil
H Power voltage lower limit
abnormality
* AC input voltage has
dropped to less than
75% of rated voltage
X Power voltage abnormal-
ity when the front cover
(upper) is opened
* An abnormal status is
detected when the
cover is opened
14 - 8
Counter
Error code
(08-400)
C471 11
C472 12
C473 13
C481 14
C480 15
- -
- -
C490 16
C474 17
C475 10
March 2005 © TOSHIBA TEC