Emerson Unidrive M400 User Manual page 78

Safety Product Mechanical
information information installation
8.1.2 RFC-A mode
Induction motor without Position feedback
Pr 00.006 {05.007} Motor Rated Current
The motor rated current parameter must be set to the maximum continuous current of the motor. The motor rated current is used in the following:
• Current limits (see section 8.3 Current limits on page 81, for more information).
• Motor thermal overload protection (see section 8.4 Motor thermal protection on page 81, for more information)
• Vector control algorithm
Pr 00.008 {05.009} Motor Rated Voltage
Pr 00.039 {05.006} Motor Rated Frequency
The Motor Rated Voltage (00.008) and the Motor Rated Frequency
(Pr 00.039) are used to define the voltage to frequency characteristic
applied to the motor (see Control Mode (00.041), later in this table). The
motor rated frequency is also used in conjunction with the motor rated
speed to calculate the rated slip for slip compensation (see Motor Rated
Speed (00.007), later in this table).
Pr 00.007 {05.008} Motor Rated Speed
Pr 00.040 {05.011} Number of Motor Poles
The motor rated speed and motor rated frequency are used to determine the full load slip of the motor which is used by the vector control algorithm.
Incorrect setting of this parameter has the following effects:
• Reduced efficiency of motor operation
• Reduction of maximum torque available from the motor
• Reduced transient performance
• Inaccurate control of absolute torque in torque control modes
The nameplate value is normally the value for a hot motor; however, some adjustment may be required when the drive is commissioned if the
nameplate value is inaccurate. A fixed value can be entered in this parameter.
When Pr 00.040 is set to 'Automatic', the number of motor poles is automatically calculated from the Motor Rated Frequency (00.039), and the
Motor Rated Speed (00.007).
Number of poles = 120 x (Motor Rated Frequency (00.039 / Motor Rated Speed (00.007) rounded to the nearest even number.
Pr 00.009 {5.10} Motor Rated Power Factor
The power factor is the true power factor of the motor, i.e. the angle between the motor voltage and current. If the Stator Inductance (05.025) is set
to zero then the power factor is used in conjunction with the Motor Rated Current (00.006) and other motor parameters to calculate the rated active
and magnetising currents of the motor, which are used in the vector control algorithm. If the stator inductance has a non-zero value this parameter
is not used by the drive, but is continuously written with a calculated value of power factor. The stator inductance can be measured by the drive by
performing a rotating autotune (see Autotune (Pr 00.038), later in this table).
78
Electrical Getting Basic Running
installation started parameters the motor
NV Media Card Onboard
Optimization
Operation PLC
Defines the maximum motor continuous current
Defines the voltage applied to the motor at rated frequency
Defines the frequency at which rated voltage is applied
Output voltage characteristic
Output
voltage
Pr 00.008
Pr 00.008 / 2
Defines the full load rated speed of the motor
Defines the number of motor poles
Defines the angle between the motor voltage and current
Advanced
Technical data Diagnostics
parameters
Output
Pr 00.039 / 2
Pr 00.039
frequency
Unidrive M400 User Guide
Issue Number: 2
UL listing
information