ASFIFF12 High Speed
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3
6.5
Parameters of Underload protection (ID’s 713 to 716):
General
The purpose of the motor underload protection is to ensure that there is load on the motor when the
drive is running. If the motor loses its load there might be a problem in the process, e.g. a broken
belt or a dry pump.
Motor underload protection can be adjusted by setting the underload curve with parameters
(Field weakening area load) and
(Zero frequency load), see below. The underload curve is a
squared curve set between the zero frequency and the field weakening point. The protection is not
active below 5Hz (the underload time counter is stopped).
The torque values for setting the underload curve are set in percentage which refers to the nominal
torque of the motor. The motor's name plate data, parameter motor nominal current and the drive's
nominal current I
H
are used to find the scaling ratio for the internal torque value. If other than nominal
motor is used with the drive, the accuracy of the torque calculation decreases.
6.6
Fieldbus control parameters (ID’s 850 to 859)
The Fieldbus control parameters are used when the frequency or the speed reference comes from
the fieldbus (Modbus, Profibus, DeviceNet etc.). With the Fieldbus Data Out Selection 1…8 you can
monitor values from the fieldbus.