Parameter 1-36 Iron Loss Resistance (Rfe)
Table 89: Parameter 1-36 Iron Loss Resistance (Rfe)
1-36 Iron Loss Resistance (Rfe)
Default value: Size related
Parameter type: Range, 0 - 10000.000 Ohm]
Change during operation: False
N O T I C E
This parameter cannot be adjusted while the motor is running.
Enter the equivalent iron loss resistance (R
Fe
) value to compensate for iron loss in the motor. The R
Fe
value cannot be found by
performing an AMA. The R
Fe
value is especially important in torque control applications. If R
Fe
is unknown, leave parameter 1-36 Iron
Loss Resistance (Rfe) on default setting.
Parameter 1-37 d-axis Inductance (Ld)
For induction motors, stator resistance and d-axis inductance values are normally described technical specifications as between line
and common (starpoint). For PM motors, they are typically described in technical specifications as between line-to-line. PM motors
are typically built for start connection.
Table 90: Parameters Related to PM Motors
Parameter 1-30 Stator Resistance
(Rs) (line to common).
This parameter gives stator winding resistance (R
s
) similar to asynchronous motor stator re-
sistance. The stator resistance is defined for line-to-common measurement. For line-line data,
where stator resistance is measured between any 2 lines, divide by 2.
Parameter 1-37 d-axis Inductance
(Ld) (line to common).
This parameter gives direct axis inductance of the PM motor. The daxis inductance is defined
for phase-to-common measurement. For lineline data, where stator resistance is measured
between any 2 lines, divide by 2.
Parameter 1-40 Back EMF at 1000
RPM RMS (line to line value).
This parameter gives back EMF across stator terminal of PM motor at 1000 RPM mechanical
speed specifically. It is defined between line-to-line and expressed in RMS value.
N O T I C E
Motor manufacturers provide values for stator resistance (parameter 1-30 Stator Resistance (Rs)) and d-axis inductance (parameter
1-37 d-axis Inductance (Ld)) in technical specifications as between line and common (starpoint) or line between line. There is no
general standard. The different setups of stator winding resistance and induction are shown in Illustration 31. Danfoss AC drives
always require the line-to-common value. The back EMF of a PM motor is defined as induced EMF developed across any of 2
phases of stator winding of a free-running motor. Danfoss AC drives always require the line-to-line RMS value measured at
1000 RPM, mechanical speed of rotation, see Illustration 32.
Line to common (starpoint)
Line-to-line values
Rs and Ld
Rs and Ld
e30bc008.12
Illustration 31: Stator Winding Setups
AU275636650261en-000101 / 130R033484 | Danfoss A/S © 2022.12
Parameter Descriptions
VLT AutomationDrive FC 301/302
Programming Guide