Dxr2 - Siemens Desigo TRA Engineering, Mounting And Installation Manual

IEC installation (International Electrotechnical Commission / International Installation Standards)
SELV / PELV
Class III
Transformer with unlimited
power
The over-current protective
device limits the energy in the
secondary circuit.
NEC Class 2 installation (National Electric Code for North America)
A
Using an energy limited
transformer with max. 100 VA
B
Using a non energy limiting
transformer (max. 400VA)
The over-current protective
devices (T 4 A fuses) limit the
energy to 100VA or less.
Multiple fuses per transformer
may be used to provide
multiple isolated secondary
circuits.
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Siemens
Building Technologies
6.3.2

DXR2

Topology: DXR2... room automation stations with AC 24 V supply can only be
wired in star topology or with stubs (no daisy chain wiring).
DXR2.E...: AC 24 V grounded or not grounded
DXR2.M...: AC 24 V
Consumption: DXR2... room automation stations with AC 24 V supply are
limited to a consumption of 4 A / 100 VA.
The devices have an internal 4 A fuse which CANNOT be replaced.
An external power supply for field devices should be fused separately for
secure operation. It must NOT be grounded.
The external power supply must NOT be used to supply the triacs.
DXR2.M...: PELV only!
must always be grounded at the transformer.
DXR2.M...:
AC 24V
400 VA
Built-
in
4A
100
VA
DXR2.M...:
Desigo TRA Engineering, mounting and installation
Wiring of power lines
must always be earthed at the transformer.
must always be grounded at the transformer.
4A 4A
~ ~
Built- Built-
in in
4A 4A
100 100
VA VA
must always be grounded at the transformer.
4A 4A
~ ~
Built-
in
4A
100
VA
CM111043en_09
2016-02-22