Network for a small to mid-sized project - Basic Documentation - DXR2.E09-101A - PXA.24M - PXC4.E16 - PXC4.E16S - PXC4.M16 - PXC4.M16S - PXC5.E003 - PXC5.E24 - PXC5.E24M - PXC5.E24S - PXC5.E40 - PXC5.E40M - PXC5.E40S - PXC7.E400L - PXC7.E400M - PXC7.E400S

Example for planning and implementing a project.

Project Description

• New office building with room automation for 136 rooms over 4 floors as well as preparing the appropriate primary plants.
• Each floor is leased by another tenant and has its own occupancy and use, i.e. the room operating mode as well as associated room setpoints, lighting per floor with central operation, and emergency function over all floors.
• Blinds control for each facade, including protection, service, and emergency function over all floors, a central weather station, demand-control of primary plants.
• Schedulers together with a calendar for room operating modes and lighting for each floor, superposed functions on a monitoring device.
• Primary plants for air handling, heat generation and distribution as well as central distribution of refrigeration on equipment rooms.
• Primary plants and general: 5 PXC4.E16-2 and 5 PXC5.E003
• Desigo room automation stations: 120 DXR2.M and 1 DXR2.E18
• Network infrastructure: Visualization and monitoring in the event of failure

Functional display of an example topology

Planning and implementation, IP network

Core level

A core switch is not needed since everything is located on one IP segment.

Distribution level

In the distribution level, in the riser zones, i.e. floor distributors:

• Unmanaged layer 2 switches are planned that are connected with copper cable
• A managed layer 2 switch is planned for network diagnostics and troubleshooting where a management platform is connected. An unmanaged layer 2 switch can be used as well if the customer has no special requirements.

BACnet MS/TP networks can have a max. cable length depending on the set baud rate. If the overall length is, however, exceeded, a new BACnet network must be created and connected via a BACnet MS/TP IP router to BACnet/IP over the Ethernet.

The rules apply again for BACnet/IP networks, i.e. the Ethernet network must be installed as an unmanaged layer 2 switch. Of course, a PXC.. can integrated in the given zones to control primary plants, depending on building planning.

IP/VLAN overview

Planning and implementation, BACnet networks

A BACnet internetwork is built using a multiple BACnet networks. All BACnet/IP capable Desigo devices communicate on the same UDP port, e.g. 0xBAC0.

The BACnet MS/TP IP router connects the BACnet/IP network to the different BACnet MS/TP networks on the floors. Note that each network must receive a unique network number.

Local and global broadcasts are not critical for this amount of devices, rooms, and plants, i.e. BBMD configuration is not required.

Each Desigo PXC.. automation station should have FDT functionality for maintenance and diagnostics and remote access.

Planning and implementation, HVAC and room automation

Plant scope:

• Desigo PXC4.E16-2/PXC7 to control primary plants.

Building scope:

• Desigo PXC5.E003 for superposed functions, e.g. scheduler for occupancy and use times by floor and monitoring Desigo room automation stations.
• Desigo DXR2.E18 for central functions over multiple floors.

Floor scope:

• Desigo DXR2.E exclusively for central functions.
• Desigo DXR2.M.. for rooms with HVAC, lighting, and blinds, or room segments with HVAC.
• PXC5.E003/PXC7/PXG3.M BACnet-MS/TP IP router.

If project implementation permits (from a cost standpoint), we recommend distributing monitoring of Desigo room automation stations or schedulers for the floors over different monitoring units (PXC5.E003).

Planning and implementation of central functions

Recommendation: Network components

• Siemens SCALANCE XB005 – Optional, as edge switch for cabling the BACnet-MS/TP IP router PXG3.M in the event the maximum cable length for the BACnet-MS/TP network is exceeded.
• Siemens SCALANCE XB005 - At the distribution level in the riser zones.
• Siemens SCALANCE XB205 - At the distribution level with port mirroring for diagnostics.

IT security and IT basic protection

The elements of infrastructure, IT systems, networks, and applications must be discussed under the aspects of security and appropriate measures need to be developed. Customer, domestic, or industry guidelines and directives must be observed under all circumstances.

For additional details, see Desigo Cybersecurity Guidelines Application Guide (A6V14142297) and Practical Guide on IP Networks in Building Automation and Control Systems (CM110668).

Summary

The following tables show how to depict all devices and network components in a small project.