Motor Thermal Protections - Vacon 100 flow Applications Manual

PARAMETER DESCRIPTIONS
If the PID feedback value is not within the supervision limits for longer than the supervision
delay, a PID supervision fault occurs.
See P3.9.1.2.
P3.9.1.11 RESPONSE TO EXTERNAL PID SUPERVISION FAULT (ID 757)
Use this parameter to select the response of the drive to a 'PID Supervision' fault.
If the PID feedback value is not within the supervision limits for longer than the supervision
delay, a PID supervision fault occurs.
See P3.9.1.2.
P3.9.1.13 PRESET ALARM FREQUENCY (ID 183)
Use this parameter to set the frequency of the drive when a fault is active and the response
to the fault is set to 'Alarm + Preset Frequency'.
P3.9.1.14 RESPONSE TO SAFE TORQUE OFF (STO) FAULT (ID 775)
Use this parameter to select the response of the drive to a 'STO Fault'.
This parameter defines drive operation when Safe Torque Off (STO) function is activated (e.g.
emergency stop button has been pressed or some other STO operation has been activated).
See P3.9.1.2.
10.10.2

MOTOR THERMAL PROTECTIONS

The motor thermal protection prevents the motor from becoming too hot.
The AC drive can supply a current that is higher than the nominal current. The high current
can be necessary to the load, and it must be used. In these conditions, there is a risk of a
thermal overload. Low frequencies have a higher risk. At low frequencies, the cooling effect
and the capacity of the motor decrease. If the motor has an external fan, the load reduction
at low frequencies is small.
The motor thermal protection is based on calculations. The protection function uses the
output current of the drive to know what is the load on the motor. If the control board is not
energised, the calculations are reset.
To adjust the thermal protection of the motor, use the parameters from P3.9.2.1 to P3.9.2.5.
You can monitor the thermal status of the motor on the display of the control panel. See
Chapter 3 User interfaces.
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.
CAUTION!
Make sure that the airflow to the motor is not blocked. If the airflow is blocked, the
function does not protect the motor, and the motor can become too hot. This can
cause damage to the motor.
LOCAL CONTACTS: HTTP://DRIVES.DANFOSS.COM/DANFOSS-DRIVES/LOCAL-CONTACTS/
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