t
t
I/I
T
105%
A
C
B
D
80%
100%
130%
Fig. 58: The calculation of the motor temperature
A. Current
B. Fault/Alarm
C. Trip area
D. Loadability
10.10.3 MOTOR STALL PROTECTION
The motor stall protection function gives protection to the motor against short overloads. An
overload can be caused, for example, by a stalled shaft. It is possible to set the reaction time
of the stall protection shorter than that of the motor thermal protection.
The stall status of the motor is specified with parameters P3.9.3.2 Stall Current and P3.9.3.4
Stall Frequency Limit. If the current is higher than the limit, and the output frequency is
lower than the limit, the motor is in a stall status.
The stall protection is a type of overcurrent protection.
NOTE!
If you use long motor cables (max. 100 m) with small drives (≤1.5 kW), the motor
current that the drive measures can be much higher than the actual motor current.
It is because there are capacitive currents in the motor cable.
PARAMETER DESCRIPTIONS
VACON · 277
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