Parameters
vacon • 145
Local contacts: https://www.danfoss.com/en/contact-us/contacts-list/
C
URRENT
LIMIT
This parameter determines the maximum motor current from the AC drive. The parameter value
range differs from size to size.
When the current limit is active the drive output frequency is decreased.
NOTE:
This is not an overcurrent trip limit.
7.2.2
Open Loop
Figure 42. Linear and squared change of motor voltage
Table 132.
Selection
number
Selection name
Description
0
Linear
The voltage of the motor changes linearly as a function of output fre-
quency from zero frequency voltage (P3.1.4.6)to the field weakening
point (FWP) voltage (P3.1.4.3) at FWP frequency (P3.1.4.2) This default
setting should be used if there is no special need for another setting.
1
Squared
The voltage of the motor changes from zero point voltage (P3.1.4.6) fol-
lowing a squared curve form from zero to the field weakening point
(P3.1.4.2) The motor runs under magnetized below the field weakening
point and produces less torque. Squared U/f ratio can be used in appli-
cations where torque demand is proportional to the square of the speed,
e.g. in centrifugal fans and pumps.
2
Programmable
The U/f curve can be programmed with three different points (see
Figure 43): Zero frequency voltage (P1), Midpoint voltage/frequency (P2)
and Field weakening point (P3). Programmable U/f curve can be used if
more torque is needed at low frequencies. The optimal settings can
automatically be achieved with Motor identification run (P3.1.2.4).
U[V]
f[Hz]
9094.emf
Un
ID603
ID602
Default: Nominal
voltage of the motor
Linear
Squared
Field
weakening
point
Default:
Nominal frequency
of the motor
