User Manual

System configuration
Integration on room level
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BACnet internetwork
A BACnet internetwork consists of one or several BACnet networks. Individual BACnet networks are
connected to BACnet routers.
Each BACnet device can communicate with another BACnet device in the internetwork. A BACnet device in
one internetwork cannot communicate with a device in another internetwork.
A Desigo management station can be used to integrate the operation of several BACnet internetworks and
other systems (see Desigo system).
When defining the system configuration, FLN integrations (LonWorks, KNX) are also added to the BACnet
internetwork. In this way, the Desigo system can be seen as a combination of several BACnet
internetworks. Technically, the individual FLN devices are not BACnet devices. They do not communicate
via the BACnet protocol.
BACnet PTP internetwork
BACnet PTP communication uses modem (telephony) or null-modem (RS232) connections. Owing to the
slow rate of data transfer via these connections, the limits are lower for a BACnet PTP internetwork.
Modem-based PTP connections are considered obsolete and are therefore no longer used. The BACnet
PTP communication connects BACnet networks via BACnet half routers.
BACnet network
A quantity of BACnet devices connected within an IP or LonTalk or MS/TP network with specific (that
means, the devices are in the same BACnet Broadcast Domain) limits. In the case of the LonTalk or MS/TP
network, the limit is physical. In the case of an IP network, the network can be physically the same, but the
limit is determined by different UDP ports.
Local communication between two BACnet devices in a BACnet network is not visible in another BACnet
network.
IP segment
Sub-area of an IP network. IP segments are connected by IP routers.
In order to ensure that BACnet communications (Broadcasts) can always take place across IP routers,
BBMDs (BACnet Broadcast Management Devices) are required. PXG3.L/M and PXC…-E.D over IP can be
configured as BBMDs. Individual BACnet devices in an IP segment can register with a BBMD as foreign
devices.
LonWorks segment (ALN)
Sub-area of a BACnet/LonTalk network. LonWorks segments are connected by LonWorks routers. In most
cases it is not necessary to divide a BACnet/LonTalk network into several LonWorks segments (ALN).
It is not possible to use a LonWorks router because of the restricted length of the data packets. An L-
Switch can be used as a router on the ALN.
LonWorks segment (FLN)
Sub-area of a LonWorks network. LonWorks segments are connected by LonWorks routers.
An L-Switch or a LonWorks router can be used as a router on the FLN.
LonWorks trunk (FLN)
Comprises all the devices connected on the FLN side of the PXC00.D/-E.D + PXX-L1…. Consists of one or
several LonWorks segments (FLN).
A LonWorks trunk (FLN) is the equivalent of a LonWorks network (FLN).
PX KNX integration
Comprises the integration of KNX devices that are connected on the FLN side of the PXC001.D/-E.D.
PX site
A Desigo PX automation system site.
The PX BACnet devices which control the plant in a PX site are interconnected via the global objects and
the primary copy procedure.