Emotron FDU 2.0 Variable Speed Drive

3.6 Thermal protection on the
motor
Standard motors are normally fitted with an internal fan.
The cooling capacity of this built-in fan is dependent on the
frequency of the motor. At low frequency, the cooling capacity
will be insufficient for nominal loads. Please contact the
motor supplier for the cooling characteristics of the motor at
lower frequency.
WARNING: Depending on the cooling
characteristics of the motor, the application,
the speed and the load, it may be necessary
to use forced cooling on the motor.
Motor thermistors offer better thermal protection for the
motor. Depending on the type of motor thermistor fitted,
the optional PTC input may be used. The motor thermistor
gives a thermal protection independent of the speed of the
motor, thus of the speed of the motor fan. See the functions,
Motor I 2 t type [231] and Motor I 2 t current [232].
3.7 Motors in parallel
It is possible to have motors in parallel as long as the total
current does not exceed the nominal value of the VSD. The
following has to be taken into account when setting the
motor data:
Menu [221]
Motor Voltage:
Menu [222]
Motor Frequency:
Menu [223]
Motor Power:
Menu [224]
Motor Current:
Menu [225]
Motor Speed:
Menu [227]
Motor Cos PHI:
The motors in parallel must have the
same motor voltage.
The motors in parallel must have the
same motor frequency.
Add the motor power values for the
motors in parallel.
Add the current for the motors in parallel.
Set the average speed for the motors in
parallel.
Set the average Cos PHI value for the
motors in parallel.
20 Installation Emotron AB 01-4428-01r2