Technical data

22
Inverter selection and dimensioning
Choosing the most suitable inverter rating
according to application needs is essential to
get the best out of Active Cube series. Too small
a rating selection may cause unsatisfactory
performance and disappointing low productivity
of the machine. Selection of too high a rating may
increase cost and generate problems in setting
motor control.
This section gives some basic hints to determine
the optimum rating and model of drive to properly
match your application requirements.
Since Active Cube is able to operate both as a
high technology “System drive” matched with
asynchronous induction motors, and as a “Servo
drive”, together with synchronous servomotors,
two different criteria are proposed:
Asynchronous induction motors (continuous load)
Active Cube is driving traditional squirrel cage
induction motors (e.g. Bonfiglioli M and BN series).
Applications are usually featured by continuous
torque supply for long time with occasional
smooth overload needs. An example of typical
torque profile is shown below.
In case of continuous torque, dimensioning and
selection of Active Cube can be done through
these steps:
a. Check mains supply phases (1 or 3 phase) and
mains supply voltage (≈230V or ≈400V)
If mains voltage is 1ph-230V or 3ph-230V
-> ACU201 series
If mains voltage is 3ph-400V -> ACU401 series
b. Check if application conditions (ambient
temperature, altitude, mains values,…) are
within rated conditions
-> in case of unusual operating conditions,
please refer to DSC for proper product
dimensioning.
c. Check rated motor current for continuous load
IN motor (see motor plate - rated current),
overload motor current required I
MAX
motor and
overload time.
Select drive rating (see data sheets in “Technical
data” section of this catalogue) applying,
together, following conditions:
- I
N
drive ≥ I
N
motor (rated drive current higher
than rated motor current)
- I
pk
≥ I
MAX
motor (overload drive current higher
than overload motor current)
- Overload time ≤ 60secs (overload time shorter
than 60secs every 10mins)
d. EMC protection class required
1. A1 -> nothing required up to 9,2kW
2. A2 -> external EMC filter required (see EMC
filters in “Accessories” section of this catalogue)
3. B -> external EMC filter required (see EMC
filters in “Accessories” section of this catalogue)
e. Input, output, feedback acquisition,
communication among drives needed?
-> Select expansion modules (see option
modules in “expansion modules” section of this
catalogue)
f. Communication with other electronic devices
(PLC,HMI,DCS,…)needed?
-> Select communication modules (see option
modules in “communication modules” section of
this catalogue)
g.Harmonicproblemsexpected?
-> Select line choke (see line choke in
“Accessories” section of this catalogue)
h. Is motor equipped with encoder or resolver
feedback device? Do we need encoder
emulation?
-> Select feedback module (see option modules
in “expansion modules” section of this
catalogue)
i. Is braking resistor required?
-> Select braking resistor (see braking resistor in
“Accessories” section of this catalogue)
Torque
Time