Lenze 8400 - Manual (Page 157)

Lenze · 8400 protec HighLine · Reference manual · DMS 3.0 EN · 03/2013 · TD05
157
5 Motor control (MCTRL)
5.4 V/f characteristic control (VFCplus)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
5.4.3.2 Adapting the Vmin boost
The V
min
boost ( C00016 ) of the motor voltage serves to select a load independent magnetising
current which is required for asynchronous motors. The torque behaviour of the motor can be
optimised by adapting the setting in C00016 .
The general linear and quadratic V/f characteristics are shown in the illustrations below. The
illustrations show the impacts of the parameters used to adapt the characteristic shape.
[5-5] Representation of the linear V/f characteristic (on the left) and quadratic V/f characteristic (on the right)

How to set the V
min
boost:
1. Operate motor in idle state at approx. 6 % of the rated motor speed.
2. Increase V
min
boost ( C00016 ) until the following motor current is reached:
Motor in short-time operation up to 0.5 n
rated
• for self-ventilated motors: I
motor
≈ I
rated motor
• for forced ventilated motors: I
motor
≈ I
rated motor
Motor in continuous operation up to 0.5 n
rated
• for self-ventilated motors: I
motor
≈ 0.8 I
rated motor
• for forced ventilated motors: I
motor
≈ I
rated motor

Note!
The V
min
boost has an effect on output frequencies below the V/f base frequency
( C00015 ).
C00015
C00016
C00015
2
C00016
2
V [V]
out
f [Hz]
V
(100 %)
rmot
1/N/PE AC 264 V
3/PE AC 264 V
3/PE AC 550 V
1/N/PE AC 180 V
3/PE AC 100 V
3/PE AC 320 V
C00015
C00016
V [V]
out
f [Hz]
V
(100 %)
rmot
1/N/PE AC 264 V
3/PE AC 264 V
3/PE AC 550 V
1/N/PE AC 180 V
3/PE AC 100 V
3/PE AC 320 V