5
05.01
5.4 Current reduction/derating
5-131
©
Siemens AG 2012 All Rights Reserved
SIMODRIVE 611 Configuration Manual (PJU) – 02/2012 Edition
5.4.4
Calculation examples
S
Supplementary conditions
Power module:
6SN1123–1AA0
j
–0EA1
Operating mode:
FD
Inverter pulse frequency:
6.3 kHz
Installation altitude
2000 m above sea level
Ambient temperature
45
°
C
X
L
= 55%
f
0
= 4.0 kHz
I
N
= 56 A
I
max
= 112 A
S
Determining the derating factors
(100% – 55%)
(6.3 kHz – 4.0 kHz)
X
T
= 100% –
8.0 kHz – 4.0 kHz
= 74.125 %
X
TU
= 100% – 2.5%
(45
°
C – 40
°
C) = 87.5%
X
H
[
85%
S
Calculating the permissible current values
I
Nred
= I
N
X
T
X
TU
X
H
= 56 A
0.74125
0.875
0.85 = 30.8 A
I
maxred
= I
max
X
T
X
TU
X
H
= 112 A
0.74125
0.875
0.85 = 61.7 A
Power module:
6SN1123–1AA0
j
–0EA1
Operating mode:
FD
Inverter pulse frequency:
6.3 kHz
Installation altitude
<1000 m above sea level
Ambient temperature
<40
°
C
X
L
= 55%
f
0
= 4.0 kHz
I
N
= 56 A
I
max
= 112 A
X
T
= 100% –
(100% – 55%)
(6.3 kHz – 4.0 kHz)
8.0 kHz – 4.0 kHz
å
I
N6.3
= I
N
X
T
= 56 A
0.74125 = 41.5 A
å
I
max 6.3
= I
max
X
T
= 112 A
0.74125 = 83.0 A
= 74.125 %
Temperature/
installation
altitude derating
Current reduction
5 Power Modules
10.04
05.08