SIEMENS
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Siemens NC 62 · 2016
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SINAMICS S120 drive system
Introduction
Line Modules
Line Modules generate a DC voltage from the line voltage and
supply Motor Modules with energy via the voltage-source DC
link. The SINAMICS S120 range includes the following types of
Line Modules:
Smart Line Modules
Smart Line Modules can feed energy to the DC link of a drive
group through a non-stabilized converter and also feed back the
generated excess energy into the power supply system. The
line voltage variations are mirrored proportionately in the DC link
voltage. Braking Modules and braking resistors are required
only if the drives need to be decelerated in a controlled manner
for island supply systems or after a power failure (i.e. when en-
ergy cannot be recovered to the supply). When a Smart Line
Module is used as the infeed, the matching line reactor must be
installed. A line filter can be installed optionally to restrict the
interference voltage level to EN 61800-3 Class C2 limits.
Active Line Modules
Active Line Modules can supply energy to the DC link bus and
return regenerative energy to the supply system. In contrast to
Smart Line Modules, Active Line Modules generate a regulated
DC voltage which remains constant despite fluctuations in the
line voltage. In this case, the line voltage must remain within the
permissible tolerance range. Braking Modules and braking re-
sistors are required only if the drives need to be decelerated in
a controlled manner even after a power failure (when energy
cannot be recovered to the supply). Active Line Modules draw a
virtually sinusoidal current from the supply which virtually rules
out any harmful harmonics. It is essential that the Active Inter-
face Module matched to the output type is used (block diagram,
see Active Line Modules in chassis format).
Active Line Modules in chassis format
All the components required to operate an Active Line Module
are integrated in the Active Interface Module. An external by-
pass contactor is required in addition for sizes HX and JX.
M
3
=
. . .
Motor
Module
Smart Line
Module
Line
contactor
Line
filter
Line
reactor
Switch
disconnector
and fuses
G_D211_EN_00033a
. . .
Motor
Module
Active
Interface
Module
Active Line
Module
Switch disconnector
and fuses or
circuit-breaker
G_D211_EN_00035b
Line filter
M
3
=
■
Overview
(continued)
© Siemens AG 2016