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Technology > Fixing > Controls > Protective function
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Protective function
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Detecting an Error Using the Thermistor
In the event of the following, the machine will set the DC power (12 V) used to drive the AC
relay (found on the fixing heater power supply PCB), thereby stopping
the AC power to the fixing heater.
•
the main thermistor (THM1)/sub thermistor1 (THM2)/sub thermistor2 (THM4) has detected
overheating.
the difference between temperature of each thermistors has deviated from a specific value.
•
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Detecting an Error Using the Thermal Switch
In response to a deviation in temperature (200 +/-5 deg C), bimetal contact of the thermal
switch (TP1; non-contact type/TP2; non-contact type) will open to cut the power supply line
(12 V) used to drive the AC relay on the fixing heater power supply PCB, thereby stopping the
AC power to the fixing heater.
Once the contact point of the Thermal Switch is open, it will not be recovered even
though the high temperature becomes to be normal temperature. Be sure to eliminate
the cause of the error, and then replace the Thermal Switch.
Once the contact point of the Thermal Switch is open, it will not be recovered even
though the high temperature becomes to be normal temperature. Be sure to eliminate
the cause of the error, and then replace the Thermal Switch.
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Technology > Fixing > Controls > Protective function
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