GE AF-650 GP Programming Manual page 39

3.3.2 F-1# Fundamental 1
Parameters to configure drive electronic overload and high/low speed limits.
F-10 Electronic Overload
Option:
3
[0] * No protection
[1] Thermistor warning
[2] Thermistor trip
[3] Electronic Overload Warning 1
[4] Electronic Overload Trip 1
[5] Electronic Overload Warning 2
[6] Electronic Overload Trip 2
[7] Electronic Overload Warning 3
[8] Electronic Overload Trip 3
[9] Electronic Overload Warning 4
[10] Electronic Overload Trip 4
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 Overload.
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. F-10 Electronic Overload to Thermistor Trip [2]
Set par. F-12 Motor Thermistor Input to Digital Input [6]
38
Function:
The frequency converter determines the motor temperature for motor protection in two different ways:
• Via a thermistor sensor connected to one of the analog or digital inputs (par. F-12 Motor Ther-
mistor Input).
• Via calculation of the thermal load, based on the actual load and time. The calculated thermal
load is compared with the rated motor current I
calculations estimate the need for a lower load at lower speed due to less cooling from the fan
incorporated in the motor.
Continuously overloaded motor, when no warning or trip of the frequency converter is required.
Activates a warning when the connected thermistor or KTY-sensor in the motor reacts in the event of
motor over-temperature.
Stops (trips) frequency converter when connected thermistor in motor reacts in the event of motor over-
temperature.
The thermistor cut-out value must be > 3 kΩ.
Integrate a thermistor (PTC sensor) in the motor for winding protection.
AF-650 GP Programming Guide
and the rated motor frequency f
M,N M,N
. The