ABB ACS480, Руководство по оборудованию, Страница: 98 / 180

￭ Notes and definitions
The ratings are valid at a surrounding air temperature of 50 °C (122 °F), with the default
drive switching frequency of 4 kHz (parameter
97.01 ), and with an installation altitude below
1000 m (3281 ft).
U
N
Nominal input voltage of the drive. For input voltage range U1, see section
Electrical power network specification (page 112) .
I
1
Nominal input current. Continuous rms input current (for dimensioning cables
and fuses).
I
max
Maximum output current. Available for two seconds every 10 minutes when
output frequency is below 9 Hz. Otherwise maximum current is 1.5 ×
I
Hd
.
Maximum current setting (parameter 30.17) can also limit the value.
I
N
Nominal output current. Maximum continuous rms output current allowed (no
overload).
P
N
Typical motor power in nominal use (no overloading). The kilowatt ratings apply
to most IEC 4-pole (400 V, 50 Hz) motors. The horsepower ratings apply to most
NEMA 4-pole motors (460 V, 60 Hz).
I
Ld
Continuous rms output current. Allows 10% overload for 1 minute every 10
minutes.
P
Ld
Typical motor power in light-duty use (10% overload). The kilowatt ratings apply
to most IEC 4-pole (400 V, 50 Hz) motors. The horsepower ratings apply to most
NEMA 4-pole motors (460 V, 60 Hz).
I
Hd
Continuous rms output current. Allows 50% overload for 1 minute every 10
minutes.
P
Hd
Typical motor power in heavy-duty use (50% overload). The kilowatt ratings
apply to most IEC 4-pole (400 V, 50 Hz) motors. The horsepower ratings apply
to most NEMA 4-pole motors (460 V, 60 Hz).
￭ Sizing
ABB recommends the DriveSize PC tool for selecting the drive, motor and gear combination
(
http://new.abb.com/drives/software-tools/drivesize ). You can also use the ratings tables.
Output derating
The load capacity ( I
N
, I
Ld
, I
Hd
; note that I
max
is not derated) decreases in certain situations.
In such situations, where full motor power is required, oversize the drive so that the total
derated output current provides sufficient current for the motor to reach the full power.
If several situations are present at a time, the effects of derating are cumulative.
Note:
• The motor can also have a derating on it.
• The DriveSize dimensioning PC tool available from ABB
(
http://new.abb.com/drives/software-tools/drivesize ) is also suitable for derating.
Example 1, IEC: How to calculate the derated current
The drive type is ACS480-04-018A-4, which has drive output current of 17 A. Calculate the
derated drive output current (
I
N
) at 4 kHz switching frequency, at 1500 m altitude and at
55 °C surrounding air temperature.
Switching frequency derating: From the table, no derating is needed at 4 kHz.
98 Technical data