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Siemens Desigo Desigo Room automation - Engineering, mounting and installation CM111043en_13
Smart Infrastrructure Wiring of power lines 2020-04-30
6.4 Power supply for field devices
Most of the TRA devices have a built-in power supply for field devices
Type TXM1.8U DXR2.x09
AC 230 V
DXR2...
AC 24 V
DXR2.x18 PXC3 RXM39.1
Data sheet N8173 N9204
N9206
N9205
N9207
N9205
N9207
N9203 N3836
AC 24 V 48 VA
5)
4 VA
2) 3)
12 VA 18 VA 48 VA 6 VA
Fusing 10 A
4) 1) 1) 1)
10 A
4) 1)
DC 24 V
2.4 W
Fusing
1)
KNX field supply
(terminals 3 and 4)
48 VA
Fusing
1)
1)
Short circuit proof.
2)
Sum of all triacs plus field supply
3)
Air quality sensors (QPA.., AQR..):
These devices require an external / local transformer.
Reason: Although the documented continuous load is only 0.5 VA, high peak
currents occur at switch on and during measurement operations.
4)
T 10 A fuse in the PXC3 / in the power supply module / in the bus connection
module.
Use cable cross section suited for 10 A according to local regulations!
5)
TXM1.8U: Bus connection module may feed any supply voltage.
Field devices may be powered using an external / local transformer.
The external transformer must NOT be grounded (earth loops).
The external power supply must NOT be used to supply the triacs.
N1 Room automation station
Y1 General device with input
DC 0...10 V, supplied by room
automation station
Y2 General device with input
DC 0...10 V, supplied externally
External supply must NOT be
earthed (earth loop)
External supply must NOT be used to
supply the triacs.
Connecting it to V~ will destroy
the room automation station
Y10
Y10
1
1
0
4
3
z
4
1
_
0
1
N1
N1
Y2
V
VV
Y1
AC 24 V
AC 230 V
Y10
N1
V
AC 24 V
AC 230 V
Y4
0..10V
OUT
Triac
24V
Note!
Caution!
Note!
Powering field devices
with external transformer