Commissioning
5-14 820XBA1097
3.Set the Vmin boost
(C016).
-
Load-independentboost of the motor voltage for field frequencies below the
U/f-rated frequency. You can thus optimize the torque performance of the inverter
drive.
-
It is absolutely necessary to adapt the asynchronous motor used, since otherwise,
the motor can be destroyed by overtemperatue:
Adjustment
Please note the thermal characteristic of the connected motor under small field
frequencies:
-
Usually, standard asynchronous motors with insulation class B can be operated for a
short time with rated current and frequencies between 0Hz
$
f
d
$
25Hz.
-
Please ask the motor manufacturer for the exact setting values for the motor
current.
A Operate the motor in idle running with a slip frequency of f
d
:
-P
mot
$
7.5 kW: f
d
5Hz
-P
mot
7.5 kW: f
d
2Hz
B Increase V
min
until you reach the following motor current:
- Motor in short-term operation at 0Hz
$
f
d
$
25Hz:
with self-ventilated motors: I
motor
$
I
N motor
with forced-ventilated motors: I
motor
$
I
Nmotor
- Motor in permanent operation at 0Hz
$
f
d
$
25Hz:
with self-ventilated motors I
motor
$
0.8
k
I
N motor
with forced-ventilated motors: I
motor
$
I
Nmotor
4.Set slip compensation
(C021).
s
n
rsyn
n
r
n
rsyn
ô
100%
n
rsyn
f
dr
ô
60
p
s Slip constant (C021)
n
rsyn
synchronous motor speed [min
-1
]
n
r
rated speed to motor nameplate [min
-1
]
f
dr
rated frequency to motor nameplate [Hz]
p Number of pole pairs
Precise setting:
Change C021 under constant load until the speed is near the synchronous speed.
If C021 is set to too high values, the drive may become instable (overcompensation).