TECO F33 Series, Инструкция по эксплуатации, Страница: 23 / 192

20 Installation
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 depend-
ent 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 char-
acteristics of the motor at lower frequency.
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:
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.
Menu [221]
Motor Voltage: The motors in parallel must have the
same motor voltage.
Menu [222]
Motor Frequency: The motors in parallel must have the
same motor frequency.
Menu [223]
Motor Power: Add the motor power values for the
motors in parallel.
Menu [224]
Motor Current:
Add the current for the motors in parallel.
Menu [225]
Motor Speed: Set the average speed for the motors in
parallel.
Menu [227]
Motor Cos PHI: Set the average Cos PHI value for the
motors in parallel.