Danfoss FC 300 Programming Manual page 45

Parameter Descriptions
3.3.10 PTC Thermistor Connection
Motor protection can be implemented using a range of
techniques: PTC or KTY sensor (see also section KTY Sensor
Connection) in motor windings; mechanical thermal switch
(Klixon type); or Electronic Thermal Relay (ETR).
Using a digital input and 24 V as power supply:
Example: The frequency converter trips when the motor
temperature is too high
Parameter set-up:
Set par. 1-90 Motor Thermal Protection to Thermistor Trip [2]
Set par. 1-93 Thermistor Source to Digital Input [6]
FC 300 Programming Guide
Using a digital input and 10 V as power supply:
Example: The frequency converter trips when the motor
temperature is too high.
Parameter set-up:
Set par. 1-90 Motor Thermal Protection to Thermistor Trip [2]
Set par. 1-93 Thermistor Source to Digital Input [6]
Using an analog input and 10 V as power supply:
Example: The frequency converter trips when the motor
temperature is too high.
Parameter set-up:
Set par. 1-90 Motor Thermal Protection to Thermistor Trip [2]
Set par. 1-93 Thermistor Source to Analog Input 54 [2]
Input
Digital/analog
Digital
Digital
Analog
NOTE
Check that the chosen supply voltage follows the
specification of the used thermistor element.
®
MG.33.M9.02 - VLT is a registered Danfoss trademark
Supply Voltage Threshold
Volt Cut-out Values
24 V < 6.6 kΩ - > 10.8 kΩ
10 V < 800Ω - > 2.7 kΩ
10 V < 3.0 kΩ - > 3.0 kΩ
3 3
45