60
Parameter Descriptions
Honeywell
9
9.8 MOTOR THERMAL PROTECTION (PARAMETERS 9.7 - 9.10)
The motor thermal protection is to protect the motor from overheating. The Honey-
well drive is capable of supplying higher than nominal current to the motor. If the load
requires this high current there is a risk that the motor will be thermally overloaded.
This is the case especially at low frequencies. At low frequencies the cooling effect
of the motor is reduced as well as its capacity. If the motor is equipped with an exter-
nal fan the load reduction at low speeds is small.
The motor thermal protection is based on a calculated model and it uses the output
current of the drive to determine the load on the motor.
The motor thermal protection can be adjusted with parameters. The thermal current
I
T
specifies the load current above which the motor is overloaded. This current limit
is a function of the output frequency.
9.7
T
HERMAL
PROTECTION
OF
THE
MOTOR
0
= No response
1 =
Warning
Fault, stop mode after fault according to parameter 2.3
If tripping is selected the drive will stop and activate the fault stage. Deactivat-
ing the protection, i.e. setting parameter to 0, will reset the thermal model of
the motor to 0%.
9.8
M
OTOR
AMBIENT
TEMPERATURE
When the motor ambient temperature must be taken into consideration, it is
recommended to set a value for this parameter. The value can be set between
-20 and 100 degrees Celsius.
CAUTION! The calculated model does not protect
the motor if the airflow to the
motor is reduced by blocked air intake grill
