Central Bus Power Supply - Siemens Synco 700 Series Basic Documentation

Introduction
Note
Power supply unit, PSU
Siemens power supply
units
Note
Building Technologies
HVAC Products
2.2.3

Central bus power supply

When one or more power supply units (PSU) are used for the bus power supply,
this is referred to as a "central bus power supply". This type of bus power supply is
required in the following circumstances:
• The permitted 8 Synco devices with DPSU (Decentral bus power supply = On")
are insufficient to cover the power consumption of the devices without a bus
power supply.
• Synco devices and third-party devices are installed on the same line.
• Only devices without a bus power supply are installed on the same line.
On a line with a central bus power supply, the following devices must not be used
to supply power to the bus:
• RM...controllers
• OZW775 central communication unit
• QAX910 central apartment unit
These Synco devices must be set to "Decentral bus power supply = Off" to prevent
them from interfering with bus communications.
Power supply units for 160, 320 and 640 mA are available. The power consump-
tion of the devices must be calculated as a means of determining the required
power supply unit, PSU (see the relevant values on the previous page).
For a line accommodating 64 bus devices, each with a power consumption of 5 mA
(64 x 5 mA = 320 mA), a power supply unit of 320 mA is sufficient.
The following power supply units from Siemens are recommended for KNX
networks (see also "GAMMA building management system").
Order codes:
• 5WG1 125-1AB01, short code N125/01
• 5WG1 125-1AB11, short code N125/11
Product data:
• Operating voltage
• Bus voltage output
For KNX networks with IP routers, the following Siemens power supply unit is
recommended.
Order code:
• 5WG1 125-1AB11, short code N125/21
Product data:
• Operating voltage
• Bus voltage output
• Output, auxiliary voltage for IP router DC 24 V (12...30 V, without choke)
For further information refer to the product description and description of functions
(enclosed with the device) or:
www.automation.siemens.com/et/gamma/
DC 29 V voltage with choke is required for the bus power supply. The DC 24 V
auxiliary voltage for the IP router requires a voltage source without choke.
Basic documentation: Communication via the KNX bus
Engineering notes
160 mA (with integrated choke)
320 mA (with integrated choke)
AC 120...230 V, 50...60 Hz
DC 29 V (21...30 V, with choke)
640 mA
AC 120...230 V, 50...60 Hz
DC 29 V (21...30 V, with choke)
21/120
CE1P3127en
30.08.2007