Aerotech BLMF Series, Руководство пользователя

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Assembly and Installation BLMF Hardware Manual
2.7.6. Thermal Protective Device
BLMF motors incorporate a positive-temperature coefficient (PTC) thermistor as a thermal protection device.
The nominal resistance of the thermistor is 100 ohms at 25°C. The thermistor exhibits a rapid increase in
resistance to 1,000 ohms as the motor temperature approaches the thermistor’s transition temperature of
100°C.
W A R N I N G : The thermal protective device used in the motor must be incorporated in an
external shutdown circuit to provide protection to the motor.
Figure 2-5: Thermal Sensor Resistance as a Function of Temperature
This thermistor can be used in a variety of different electronic interfaces. A precaution when using this type
of device in an interface circuit is to avoid self-heating effects. An excessive amount of current through the
thermistor will cause its temperature to rise and a false triggering will occur.
Figure 2-6: Typical Thermistor Interface Circuit
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