Ricoh MT-C1 Service Manual page 441

15 February 2006
543 A Fusing lamp overheat error 1 (software)
Central thermistor detected a
temperature of 240°C at the center
of the hot roller. Fusing temperature
control software error
544 A Fusing lamp overheat error 1 (hardware)
The central thermistor or an end
thermistor detected a temperature
of 250°C on the hot roller.
545 A Fusing lamp overheat error 2
After hot roller reaches warmup
temperature, the fusing lamps
remained on at full capacity for 11
samplings (1.8 sec. duration) while
the hot roller was not rotating.
547 D Zero cross signal malfunction
One of the following conditions is
detected 10 times:
• When the main switch is on, the
frequency measured by the
number of zero cross signals for
500 ms is larger than 66Hz or
smaller than 45 Hz.
• The interval between one zero
cross signal and the next is 7.5
ms or shorter 3 times
consecutively for 500 ms.
550 A Fusing Web End
Web end detected 5 times within
500 ms and web motor continues to
rotate 40 s. If web end is detected
for another 500 ms, then the SC is
logged.
551 A Fusing thermistor error 1
The end thermistor (contact type)
was less than 0C (32F) for more
than 7 seconds.
552 A Fusing thermistor error 2
The end thermistor (contact type)
could not detect:
• 100°C 25 seconds after the start
of the warmup cycle.
• A change in temperature more
than than 16 degrees for 5
seconds.
• The reload temperature with 56
seconds after the start of the
fusing temperature control cycle.
B140/B246 SERIES SERVICE MODE
• PSU defective
• IOB defective
• BICU defective
• PSU defective
• IOB defective
• BICU defective
• Thermistor damaged, or out of position
• Fusing lamp disconnected
• Noise on the ac power line
• Web end (requires replacement)
• Web end sensor defective
Note: After replacing the web with a new
one, reset SP1902 001 to "0" to release
SC550.
• Thermistor disconnected
• Thermistor connector defective
• Fusing lamp disconnected
• Thermistor bent, damaged
• Thermistor position incorrect
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