DESIGO building automation system

DESIGO PX OPEN
The native BACnet automation station PX OPEN is a multifunctional integration
platform used to connect third-party automation stations and open field-bus
networks to the BACnet network.
• PX LON for the connection of LONWORKS devices and networks and the
DESIGO RXC room automation system.
• PX Modbus, PX M-bus and PX SCL (Structured Control Language) to connect
Modbus, M-bus or simple ASCII protocols for RS232 or RS485 (free SCL
programming).
• PX KNX to connect KNX S-mode (EIB) devices and networks, DESIGO RXB and
RXL room automation as well as Synco 700.
The data points of the third-party are mapped to input/output functions in BACnet
and are then available as fully communicating data points for further processing
and further connection, e.g. for:
• Alarm handling and prioritization.
• Override control, priority control and commands for central operation.
• Grouping
• Time schedules
• Trend logging
PX OPEN integrates up to 2000 items of information per device. The bi-directional
exchange of data is event-driven, i.e. the systems only exchange information if the
data point changes. Peer-to-peer communication can be implemented without
difficulty in the BACnet network
The PX OPEN integration stations are positioned in a flexible configuration in the
BACnet network and can be operated via the local LCD operator units.
"Simple" protocols based on ASCII strings can be connected directly to PX OPEN
by use of SCL in conjunction with a freely programmable RS232 or RS485 port.
Vendor-neutral protocols
• BACnet
• LONWORKS
• KNX S-mode (EIB)
• M-bus
• Modbus
Vendor-specific protocols, e.g.
• Hotel management: Fidelio.
• Siemens AlgoRex (fire detection system).
PX LON
PX LON connects LONWORKS networks to DESIGO and maps LONWORKS network
variables to BACnet data points.
Main functions of PX LON
• Compression of DESIGO RXC room
controller data and third-party devices.
• Maps DESIGO RXC applications to BACnet
for operation and monitoring (grouped as
HVAC, lighting and blind control functions).
• Higher-level control and optimization
functions, such as room and zone-based
groups, time control, and system functions
such as changeover, summer/winter
compensation etc.
• Alarm handling, device monitoring.
• Trend storage.
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Siemens DESIGO Building automation and control system CM110660en_03
Building Technologies
System description