SIEMENS
SINAMICS DCM
Engineering information
Parallel connection
5/19
Siemens D 23.1 · 2014
5
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Overview
Parallel connection of SINAMICS DC MASTER units
SINAMICS DC MASTER units can be connected in parallel to
increase the power rating.
The following secondary conditions must be fulfilled:
The hardware and plug connectors necessary to transmit the
firing pulses and to establish the higher-level communication are
provided on the CUD.
A maximum of 6 units can be connected in parallel. When
connecting several units in parallel, the master unit should be
positioned centrally due to the signal runtimes. Maximum cable
length of the parallel-connection interface cable between master
and slave units at each end of the bus: 15 m.
Identical, separate commutating reactors (
u
K
min. 2 %) are
required for each SINAMICS DC MASTER unit in order to evenly
distribute the current. The difference in reactor tolerances deter-
mines the current distribution. For operation without derating
(current reduction), a tolerance of 5 % or better is recom-
mended.
Only units with the same DC current ratings are permitted to be
connected in parallel.
The permissible output current when connecting units in parallel
is, when maintaining the secondary conditions:
I
max
=
n
×
I
N(SINAMICS DC MASTER)
n
= number of SINAMICS DC MASTER units
Redundant operation (mode "(n+m) operation")
SINAMICS DC MASTER can also be used in a redundant con-
figuration as a special operating mode of the parallel connec-
tion. In this operating mode, it is possible to maintain operation
with the remaining SINAMICS DC MASTER units if one unit fails
(e.g. if a fuse fails in the power section). When appropriately
configured and interconnected, both the armature circuit as well
as the field circuit can be redundantly operated.
SINAMICS DC MASTER units that can still function, continue to
operate without any interruption when a unit fails. When config-
uring the system, it is important to note that in redundant appli-
cations, the power rating of only n units (instead of n+m units)
must be sufficient.
In the case of a fault, the master functionality is automatically
transferred. As a consequence, this operating mode is possible
both when power sections of the slaves fail and when the power
section of the master fails. (MTBF data in redundant operation
are available on request.)
Connection schematic of the armature circuit when connecting SINAMICS DC MASTER units in parallel
(1)
The same phase sequence is required between 1U1/1V1/1W1.
(2)
The same phase sequence is required between 1C1/1D1.
(3)
The units are connected using (8-pin) shielded patch cables of type
UTP CAT5 in acc. with ANSI/EIA/TIA 568, such as those that are used
in PC network technology. A standard 5 m long cable can be directly
purchased from Siemens (Article No.: 6RY1707-0AA08). (n-1) cables are
required to connect n units in parallel. The bus termination must be
activated at the units/devices connected at the start of the bus and at
the end of the bus.
(4)
These fuses may only be used with units up to 850 A.
(5)
Only for units up to 850 A in four-quadrant operation.
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More information
For further information and application documents, please
go to the following website address:
siemens.com/WW/view/en/38157755/130000
(Entry type "Application")
3 AC 50/60 Hz
400 V ... 950 V
4U1
X165
X177
-13 -12 -9
X166
X165 X166
X165 X166
3C 3D(1D1)
1C1 1D1
3C 3D(1D1)
1C1 1D1
3C 3D(1D1)(1C1)
1C1 1D1
4V1
4W1
5N1
5W1
5U1
3U1
3W1
1U1
1V1
1W1
4U1
4V1
4W1
5N1
5W1
5U1
3U1
3W1
1U1
1V1
1W1
4U1
4V1
4W1
5N1
5W1
5U1
3U1
3W1
1U1
1V1
1W1
SINAMICS DC MASTER
(Slave)
SINAMICS DC MASTER
(Slave)
SINAMICS DC MASTER
(Master)
Fan
Field
Armature
Power
supply
Power
supply
Power
supply
Fan
Field
Armature
Fan
Field
Armature
X177
-13 -12 -9
X177
-13 -12 -9
(1C1)
(1C1)
OFF1
Enable
G_D023_EN_00009a
(5)
(2)
(3)
(5)
(2)
(5)
(2)
(3)
(3)
(1)
(1)
(1)
(4)
(4)
(4)
M
© Siemens AG 2014