Typical projects - Planning - PXC4.E16 - PXC4.E16-2 - PXC4.E16S - PXC4.E16S-2 - PXC4.M16 - PXC4.M16-2 - PXC4.M16S - PXC4.M16S-2 - PXC5.E003 - PXC5.E24 - PXC5.E24M - PXC5.E24S - PXC7.E400L - PXC7.E400M

Typical projects

Overview

The structure of the BACnet network in building automation projects depends on:

topology
type and number of devices
requested functionality such as interaction in the whole site
project IT infrastructure to be used.

This chapter is structured in small, medium, and large automation controls projects accordingly and covers the automation range PXC4…7 with integration of clients and up to 250 BACnet devices (PXC, DRA, and third-party).

For system topologies with a higher number of primary controls automation stations PXC4…7 and/or room controllers (DRA/third-party) with more than 250 devices in total, see Application guide for BACnet networks in building automation and control, A6V11159798.

BACnet Secure Connect versus BACnet/IP

The topologies below illustrate the physical cabling structure of a typical BACnet/IP project. Projects using BACnet Secure Connect instead of BACnet/IP must also consider the following points:

BACnet/SC devices also have a logical topology: Each BACnet/SC device (“node”) must be logically linked to a dedicated BACnet/SC “hub”.
This node-hub-link is a purely logical concept with no direct 1:1 correlation to underlying structures for physical cabling. All BACnet/SC communication of nodes is routed through the hub. As a consequence, do not install hubs on low-bandwidth or high-latency points within the overall network.
BACnet/SC is its own BACnet-datalink (similar in concept to BACnet MS/TP or BACnet/IP). As a result, BACnet/SC and non-BACnet/SC components of the network must be connected by a BACnet router in between. Any PXC5/7 automation station that supports BACnet/SC as a hub may act as a BACnet router.

For more information on BACnet/SC, refer to Application guide for BACnet networks in building automation and control, A6V11159798.

Small automation control projects

Small automation control projects with:

Some primary plants
Some touch panels
Some KNX PL-Link field devices
Total number of data points (physical and integration): 50 to 300
Total number of devices (PXC, DRA, and third-party): up to 20
Optional: Cloud connectivity to Building X for remote access and data points time series

Examples: Small schools, small office buildings, etc.

Installation

Cabling: Patch cables (CAT5/6/7 up to 100 meters) between PXC devices. Each PXC4/5/7 device has a switch with two ports for easy connection. Protect cabling against unauthorized access.
Connection to ABT Site Tool either as indicated on the onboard switch or via WLAN.

Set up network information for each device (via ABT Site Tool):

Each PXC device needs a unique address
IP port: Default value BAC0

Mid-size automation control project with Desigo Control Point

Mid-sized automation controls project with:

Desigo Control Point embedded building operations with touch panel operation
Primary plants
KNX PL-Link field devices
Integration
Optional: A few room controllers
Total number of data points (physical and integration): 200 to 1000
Total number of devices (PXC, DRA, and third-party): 5 to 50
Optional: Cloud connectivity to Building X for remote access and data points time series

Examples: Small to mid-sized schools, office buildings, retail buildings, etc.

Patch cables

Installation cables

Installation of local and distributed devices

Cabling: Patch cables (CAT5/6/7 up to 100 meters) between PXC devices. Each PXC4/5/7 device has a switch with two ports for easy connection. Protect cabling against unauthorized access.
Installation cables (shielded twisted pair (TP) cables with solid copper wiring).
- BACnet IP network: Maximal length 90 m between patch panels.
- Modbus RTU: Maximal length 800 m between PXC and last Modbus device.
Installation cables (fiber optics).
- BACnet IP network: Maximal length of 2000 m between patch panels. Refer to the manufacturer’s specification.
Other installation variants and additional technical information:
- See Application guide for IP networks in building automation and control, A6V10630964.

Network setup (own IP network)

Set up of the network information for each device (via ABT Site Tool):

Each PXC device needs a unique address
IP port: Default value BAC0

Network setup (using existing IP network with DHCP server)

Enable “DHCP” (an individual address for each PXC device is not necessary since the DHCP server assigns the addresses).
IP port: Default value BAC0

Modbus TCP / RTU devices

The Modbus data points (register) for the different devices are mapped to BACnet input/output objects in the PXC4, PXC5, and PXC7 and time for the values are updated as per the selected polling time.

These objects are handled in the system as BACnet input/output objects similar to objects from other subsystems (e.g. TXM modules).

Desigo Control Point (embedded building operations and touch panels)

For details, see Desigo Control Point Basic documentation, A6V11170804.

Mid-size to large automation control projects with Desigo CC

Large automation controls project with:

Desigo CC Management Platform
Primary plants
KNX PL-Link field devices
Integration
Optional: room controllers
Total number of data points (physical and integration): 500 to 10,000
Total number of devices (PXC, DRA, and third-party): Up to 250
Optional: Cloud connectivity to Building X

Examples: Large schools, large office buildings, large retail buildings (shopping malls)