External Bus Supply - Siemens Desigo TRA Engineering, Mounting And Installation Manual

Parallel operation
Siemens power supply
units
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12.1.2 External bus supply

If the 160mA of the PXC3 / the 50 mA of the DXR2 are insufficient to cover the
power demand of the connected devices, the internal bus power supply must be
switched off via tool and replaced by an external bus power supply unit (PSU).
Power supply units for 80,160, 320 and 640 mA available in specialty stores. The
total power supply for the devices must be calculated to determine the appropriate
size. Comply with the corresponding details in the datasheet.
A 640 mA power supply unit suffices for a line featuring 64 devices on the KNX bus
with an average power demand of 10 mA each.
Parallel operation of external bus supplies with the internal bus supply of a
room automation station is NOT allowed.
In principle, parallel operation of external bus supplies among themselves is
possible. However, check if the specific PSU is allowed to be operated in parallel
with other PSUs. Refer to the technical specifications.
Depending on the type, a minimum cable distance is required between two PSU,
see section 12.3. Siemens PSU may be placed without a distance
We recommend the following Siemens power supply units for KNX networks (see
links below).
5WG1 125-4AB23, short designation RL125/23
(with integrated throttle)
5WG1 125-4CB23, short designation JB 125C23
(with integrated throttle)
5WG1 125-1AB02, short designation N125/02
(with integrated throttle).
5WG1 125-1AB12, short designation N125/12
(with integrated throttle).
5WG1 125-1AB22, short designation N125/22
(with integrated throttle).
Operating voltage
Bus supply output
Product and function description (inserted with each device).
Technical product information:
https://www.hqs.sbt.siemens.com/cps_product_data/data/search_find_en.htm?t
e1=5WG1
Desigo TRA Engineering, mounting and installation
KNX PL-Link room bus
Parallel operation with other PSUs is allowed
Parallel operation with other PSUs is allowed
Parallel operation with other PSUs is allowed
Parallel operation with other PSUs is allowed
Parallel operation with other PSUs is allowed
AC 120...230 V, 50...60 Hz
DC 29 V (21...30 V, throttled)
80mA
80mA
160 mA
320 mA
640 mA
CM111043en_09
2016-02-22