3.3.2 F-1# Fundamental 1
Parameters to configure drive electronic overload and high/low speed limits.
F-10 Electronic Overload
Option: 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
M,N
and the rated motor frequency f
M,N
. The
calculations estimate the need for a lower load at lower speed due to less cooling from the fan
incorporated in the motor.
[0] * No protection Continuously overloaded motor, when no warning or trip of the frequency converter is required.
[1] Thermistor warning Activates a warning when the connected thermistor or KTY-sensor in the motor reacts in the event of
motor over-temperature.
[2] Thermistor trip 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 k.
Integrate a thermistor (PTC sensor) in the motor for winding protection.
[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]
AF-650 GP Programming Guide
38
3
To Next Page
Loading...
