Permissible Duty Cycles/Derating - Siemens Simodrive 611 Configuration Manual

02.12 02.07
05.01
6.4.2

Permissible duty cycles/derating

Nominal load duty
For a derating, it must be analyzed as to the reason why this is required, and
cycles for NE
which component is involved. For instance, if derating is required as a result of
modules the line voltage, then for uncontrolled infeed modules, the maximum motor
speed must be correspondingly adapted.
P
P
max
P
s6
P
n
4 min
0.4 P
n
10 min
S6 load cycle with pre–load condition
P
P
max
P
n
0.2 s
10 s
Peak power load duty cycle with pre–load
Fig. 6-10 Nominal load duty cycles for NE modules
Calculation of
The effective load must be determined over a load period/cycle and this must
maximum be set to the ratio for the rated power of the module. The resulting weighting
factor B must not exceed the factors of the associated time interval T indicated
permissible line
in Table 6-11. Note that the maximum P
infeed load
and the derating factor, depending on the pulse frequency and/or installation
altitude, must be taken into account!
As a rule of thumb, the following applies for block-type load duty cycles:
B =
T
P
P
t
1
B
© Siemens AG 2012 All Rights Reserved
SIMODRIVE 611 Configuration Manual (PJU) – 02/2012 Edition
P
P
max
P
s6
P
n
0.4 P
n
t
Peak power load duty cycle with pre–load
P
F  P
n
P
n
t
Peak power load duty cycle without pre–load
F: For all NE modules up to Pn v 80 kW, F = 1.6 applies
For Pn = 120 kW, F = 1.4 applies (F = factor)
 
2 2
t + t +...+
P P
1 1 2 2
T  P 2
n
Total duration of the load duty cycle
Rated power of the I/R module
n
...P Magnitude of the required power
1 k
...t Duration of the corresponding power
k
Evaluation factor for the load duty cycle according to Table 6-11
6 Infeed Modules
6.4 Technical data
10 s
t
60 s
4 s
10 s
must not be exceeded at any time
max

2
t
P
k k
t
6-169
6