Advantech Automation1 XC4, Hardware Manual

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2.3.3. Thermistor Input
The thermistor input is used to detect a motor over temperature condition by using a positive
temperature coefficient sensor. As the temperature of the sensor increases, so does the resistance.
Under normal operating conditions, the resistance of the thermistor is low which will result in a low input
signal. As the increasing temperature causes the thermistor’s resistance to increase, the sensor will
trigger an over temperature fault.
The thermistor is connected between Pin 2 and Signal Common. The nominal trip value of the sensor is
1.385 kΩ. The circuit includes a 12 kΩ internal pull-up resistor which corresponds to a trip voltage of
+0.52 V.
Table 2-20: Thermistor Input Pin on the Feedback Connector
Pin # Description In/Out/Bi
2 Motor Over Temperature Thermistor Input
Figure 2-26: Thermistor Input Schematic (Feedback Connector)
2.3.3. Thermistor Input XC4 Hardware Manual
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