1
05.01
1.3 Engineering a drive
1-31
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Siemens AG 2012 All Rights Reserved
SIMODRIVE 611 Configuration Manual (PJU) – 02/2012 Edition
1.3
Engineering a drive
The power modules are selected depending on the motors to be used and the
drive requirements (torque, speed ratio).
The infeed module is selected using the DC link power required by the group
and the active power requirement of all of the power modules:
S
Taking into account the coincidence factor (value determined from the load
duty cycle or experience value). Not all of the motors are subject to a full
load at the same time.
––> refer to Fig. 1-6
S
The maximum permissible power to charge the DC link capacitors.
––> refer to Chapter 6.6 and Table 1-4
When calculating the DC link power P
ZK
, refer to Fig. 1-6.
In this case it must be noted that the DC link will be over–dimensioned if the
motor outputs are simply added together:
S
Because, from experience, feed axes are not operated at their rated torque
and rated speed
S
Because generally, the feed drives are not simultaneously operated
In the engineering sheet (refer to Fig. 1-6) to calculate the DC link power, these
factors are taken into account by the speed ratio ñ/nN (ratio between the oper-
ating speed and the rated speed) and coincidence factor K.
Gating and electronic points used to determine the load limits of the power sup-
ply. It is not possible to specify the power rating of an individual voltage source
as several power supplies are coupled with one another. If the number of gating
or electronic points is exceeded, an additional power supply must be used – the
”monitoring module”.
When determining the gating (AP) and electronic points (EP) refer to Chapter 6.6.
When calculating the power supply rating, refer to Chapter C.1.1.
Every infeed module has a maximum value that applies when expanding the
DC link capacitors. It must be ensured that the DC link capacitance in the se-
lected drive group is not exceeded (refer to Table 1-1).
The sum (total) of the DC link capacitances (refer to Chapter C.1.1, Table 1-4) of
all modules must be less than or equal to the charge limit corresponding to the
following table of the infeed modules:
Dimensioning
Feed axes
Power supply
rating
DC link
capacitance
1 Overview of the Drive System
10.04
02.07
02.07
