Protocolli LonWorks - University of Urbino · node B node C &&& Structure of a Network Variable ......

Corso “DOMOTICA ED EDIFICI INTELLIGENTI” – UNIVERSI TA’ DI URBINODocente: Ing. Luca RomanelliMail: [email protected]

Domotica ed edifici intelligenti – Università di Urbino 1

Protocolli

LonWorks

� LON

� Echelon

� LONWORKS

� LONWORKS Protocol

� LONMARK

- LLLLocal OOOOperating NNNNetwork

- Inventors of the technology

- Collective term for the technology

- Communication protocol

- Interoperability standardization committee

Concept DefinitionsConcept DefinitionsConcept DefinitionsConcept Definitions


� LONMARK

� Node

� Neuron

� SNVT

� SCPT

� LNS

� XIF-File

- Interoperability standardization committee

- Device

- Chip in the network node

- Standardized Network Variable Type (said Snivit)

- Standardized Configuration Variable Type (said Skipit)

- Local Network Services – a network access method

- Definition file of a network variable - Interfaces

What is L ONWORKS® Technology?

-LON (Local Operating Network) is a decentralised control network forbuilding automation, in industry, in transport, in telecommunications andin many other areas.

-The communication of intelligent sensors, actuators and operator units


-The communication of intelligent sensors, actuators and operator unitsof a LON® network is the result of a protocol already implemented in the Neuron ®-Chip , this is the LonTalk® protocol.

� LONWORKS networks display an event controlled system with decentralised intelligence.

� Contrary to conventional DDC technology all information is not immediately available since the network inputs are only updated after an event change of the sender.

Philosophy of L ONWORKS® Networks


after an event change of the sender.

� LONWORKS nodes are not normally able to sample (or poll) the connected nodes to check if they have information.

� LONWORKS nodes communicate via network variables which are logically connected together.

InformationInformationInformationInformation----based Systembased Systembased Systembased System

Motion

Room occupied

BrightnessFeedback

Temperature

Setpoint


The The The The sensors sensors sensors sensors in a LonWorks network make their information available.in a LonWorks network make their information available.in a LonWorks network make their information available.in a LonWorks network make their information available.

Actuators Actuators Actuators Actuators processprocessprocessprocess this information as required.this information as required.this information as required.this information as required.

0%-100%

21°C

Setpoint


Motion

Room occupied

BrightnessFeedback

Temperature

Setpoint


The allocation of the individual network variables is established using a soThe allocation of the individual network variables is established using a soThe allocation of the individual network variables is established using a soThe allocation of the individual network variables is established using a so----called called called called Binding.Binding.Binding.Binding.

0%-100%

21°C

Setpoint


Motion

Room occupied

BrightnessFeedback

Setpoint

Temperature

Setpoint


Function enhancement is implemented in newly added devices. Therefore interruption of the remaining Function enhancement is implemented in newly added devices. Therefore interruption of the remaining Function enhancement is implemented in newly added devices. Therefore interruption of the remaining Function enhancement is implemented in newly added devices. Therefore interruption of the remaining

functions when extending a network is mostly not necessary.functions when extending a network is mostly not necessary.functions when extending a network is mostly not necessary.functions when extending a network is mostly not necessary.

Intruder

Aktive / inaktive

Key Code

0%-100%

21°C

Setpoint

Bindings are in no way intelligent !

node A

Logical functionality must always be realised in the Logical functionality must always be realised in the Logical functionality must always be realised in the Logical functionality must always be realised in the

actuatoractuatoractuatoractuator


node B

node C

&&&&

Structure of a Network Variable

� For communication via network variables it is essential that only network variables of the same type are connected together.

� Every network variable consists of a Name and a Type, but the Name is purely a description.


NV NameNV Type

nvoOutsideTempSNVT_temp_p

Connection between network variables

Network variables behave like coded plugs

SNVT_temp_p SNVT_temp_p


SNVT_temp_p

SNVT_temp SNVT_temp

SNVT_temp X

Network Variables

� Generally there are two different types of network variables:

� SNVT = Standard Network Variable Type

� UNVT = User-defined Network Variable Type


Network Variables

� Generally a LON node has an input network variable and an output network variable (nvi.. and nvo..).

� Input network variables are used to accept information from other LON partners.

� Input network variables can also be defined by the manufacturer


� Input network variables can also be defined by the manufacturer as configuration variables. These are used at the same time to store the settings in a non-volatile memory.

� Output variables are also used to forward information to another partner on the LON network.

� Output network variables must be set in the program, they cannot be manually controlled.

Options for Message Services

� Unacknowledged

Unacknowledged sending of messages on the network.

� Unacknowledged Repeated

Unacknowldeged sending of messages on a network with a


Unacknowldeged sending of messages on a network with a repeat function, to make the transfer more secure.

� Acknowledged

Acknowledged sending of messages on the network, in which the sender waits for confirmation from the receiver, which says that the receiver has received the message. If there is no confirmation then the message is repeated.

Options for Message Services

� Request Response

This is also a confirmed service but with which the receiver queries information from a node

This service is usually only used with gateways which query the LON nodes. (PXR in polling operation, OPC, ....)


Node Addresses

� Neuron IDEach LON node has a unique identifier (Neuron ID). This identifier is usually only used on installation of a LON node. In this way each node gets a unique logical address in the network.

� Domain / Subnet / Node AddressesEach LON network has its own domain. In this domain the


nodes are distributed in different subnets, depending on the number of nodes and the structure of the network. In each subnet all nodes have their own unique node number.

Domain

Subnet 1

Node 1 Node 127

Subnet 255

Node 1 Node 127

Domain ID

Subnet ID

Node ID

Types of Addresses

� LON communication mainly uses the following methods of addressing:

� Subnet / Node Adressingnormally used when a node speaks directly to another node.

� Group Adressing


� Group Adressingnormally used when a node speaks simultaneously to more than one node.

� Broadcast Adressingused when a node speaks simultaneously to more than one node but because of the restrictions in the LON chip, it is not possible to use group addressing.

Heartbeat

� LON nodes send their information on the network partially cyclical with a so-called heartbeat.

� LON nodes expect a heartbeat on their input variables. If this cyclical heartbeat is not received then many nodes use their own saftey value instead of the value on the network variable.


Example DESIGO RX:If the Occupied message is not received for a long time then the node changes automatically into the Occupied status.

� General cyclical sending to all variables can however also be critical, since, for example, configuration variables such as setpoints are saved in the flash memory. Perpetual cyclical writing would destroy the flash memory!

Transceiver

� Devices in LON networks have different transceivers, some ofthis are:

� FTT-10ATransmitter for LON node with its own voltage supply.

� LPT-10


� LPT-10Transmitter for LON node which obtains its voltage supplyfrom the LON bus.

� Use of both types of transceivers is allowed.

Number of LON Nodes in the Network

� The following format can be used to work out the maximum number of nodes allowed per network segment:

(Number of FTT*2) + (Number of LPT) ≤ 128

Background for the limitation is not the addressing requirement


Background for the limitation is not the addressing requirement but the load on the bus.

� If the number of permissible nodes in the segment is exceeded then extra infrastructure components are needed.

Link Power

� LON nodes without their own voltage supply receive their voltage from a LINK Power voltage supply.

These devices supply the LON bus with 42V d.c. voltage and always contain a built-in bus terminator.


Repeater

� Repeater (physical repeater)

� Simply forwards all packets between two channels� Has no memory� Only one repeater is allowed per channel� 2-way and 3-way repeaters� Option to include terminators


� Option to include terminators

� Physical repeaters repeat everything – even disturbances !!!

Repeater

� Repeater (logical Repeater)

� Receives the whole message in memory� forwards all the packets if configured as a bridge, but only if the domain

IDs are in agreement� transparent


� Limitations:

� Time delay for transmission of data� 100 messages per second (reduced bandwidth) in comparison to

FTT10A with 320 Messages per second

� Router

� Interface between different media.

� learning Router� Monitors the data traffic and „learns“ the topology on the level of the domains /

subnets. Packets are then forwarded selectively between channels.� Attention!: If a network is modified then a learning router must be reset.

Router


� configured Router� Here the internal routing table is defined using a network management tool.

� Limitations:� Time delay for transmission of data� 100 messages per second (reduced bandwidth) in

comparison to FTT10A with 320 Messages per second

� L-Proxy� Interface between separate LON networks

� Connection to different domains� Guaranteed limitation for system integrators� Several LON devices in one box� Separate commissioning for each manufacturer possib le

LON Proxy Node


� Separate commissioning for each manufacturer possib le� Simple mapping of the required network variables us ing external

configuration files� Dynamic network interface� Extra properties such as active polling ,

or extension of the Neuron-Chip limitations using addressing

Network Interface

� It is necessary to install a network card in the PC to be able to access the network with the commissioning tool

� A built-in LON card is usually used in desktop PCs

� PCLTA (Echelon)


� PCLTA (Echelon)

� For Laptops there is an array of other network cards:

� PCC10 (Echelon)� PCMCIA Card

Attention : this card does not function with all La ptops!

Network Interface


� XLON-USB (DH Electronics)� USB Interface

� NIC-USB (Loytec)� USB Interface with the possibility running of 8

simultaneous applications multiplexed on one interface. An LPA Analyser can also be registered on this hardware.

LON Node Summary

� A LON node can typically have up to 62 network variables.

� A network node has only a maximum of 15 address table entries. This puts a limit on addressing and in the group memberships.


� Node for our applications have a Transceiver FTT-10A or LPT10. Other transceivers are not compatible.

Interoperability

� LONMARK Interoperability Organisation campaigns for interoperability between the different applications

� Interoperability guidelines for development of LON applications are published by the LONMARK Interoperability Organisation


� LONMARK objects and functional profiles for different applications are compiled by LONMARK

� LONMARK certifies LON nodes with the LONMARK Logo

Interoperability

� The basis for interoperability is the strict use of SNVTs

� SNVTs are also fixed by LONMARK and published in a

SNVT Master List

� In the Master List the network variables, range of values,


� In the Master List the network variables, range of values, resolution, etc are defined.

� SNVT Master List is a living document!

Attention: Newer versions are backwards compatible, but not the other way round. So, it may happen that, for example, a new variable is added or the value range from existing variables is extended.

SNVT Master List


SNVT Master List

state

0 .. 100%

Percent resolution 0,5%

Values according toTable

value

SNVT_switch

No.95


Value Command Remark

0 OFF

Inactive

Command On

Command Off

ON

ZERO

1

0xFF

Structure

2 byte

SNVT Master List

-273,17 .. 327,66°C

Temperature

Resolution 0,01°C

value

SNVT_temp_p

Nr.105


Signed_long

2 byte

SNVT Master List

setting rotation

0 .. 100% -359.98 .. 360.00 Grad

Angle resolution

0.02 degreesPositioning

Listing

function

SNVT_setting

Nr.117


Value Command Remarks

0 SET_OFF

Command Down

Positon to a value

Command Up

Command On

Command Off

Stop

Inactive

SET_ON

SET_DOWN

SET_UP

SET_STOP

SET_STATE

SET_NUL

1

2

3

4

5

0xFFStructure

4 byte

Interoperability

� The exclusive application of SNVTs however does not guarantee interoperability

� Only the network variables are defined in the Master List, not their applications – this means that different manufacturers could, for example, interpret individual values


manufacturers could, for example, interpret individual values differently.

� In the past this often happened with applications concerning blinds. This demands caution when working on existing projects.

0% 90%- 90%

90% 180%0%

0% 90%- 90% 0% 90%- 90%

90% 180%0% 90% 180%0%

Example: Blinds

Interoperability


node A node B

snvt setting snvt setting

node A node B

snvt setting snvt setting

The value of the angle of the blind

can be interpreted differently by

different manufacturers

LONMARK Objects

Sensor, ControlObject Type Nr. 2

nv3

nv1 nv2nviValueFbSNVT_xxx

nviPresetFbSNVT_preset

nvoValueSNVT_xxx

nv5nvoPresetSNVT_preset


nc17 – Location Descriptionnc31 – Amplification Factornc26 - Offsetnc20 - max. Rangenc23 - min. Rangenc27 – for sending Delta nc22 - max. Sending Time nc24 - min. Sending Timenc16 – Invert Outputnc28 – Conversion Table Xetc.

� Implementation of configuration properties:

� using configuration network variables (nc#)

� using direct memory access SCPTs (only with Neuron-Chip-Hosts!)

� using SCPTs which use LonTalk file transfer protocol

Configuration properties versus network variables (nc#):

Configuration Properties


� Configuration properties versus network variables (nc#):

� applying configuration properties the (limited) number of network variables which can be declared on a node isnot restricted!

� configuration properties can be any length and can contain any size of array (limited by the available memory)

� an individual SCPT can be used by several objects (Engineering!)

• LONMARK®-Objects• Pre-defined software templates which can be used to describe the device behaviour.•For CommunicationNetwork VariablesSNVTS•For Installationpre-defined Format for self-documentation•For Optimizationpre-defined format for the definition and calibration of

FunctionProfile

Device

LONMARK Function Profiles


pre-defined format for the definition and calibration of configuration parameters

•Function ProfilesA collection of LONMARK® ObjectsCommon method to define clearly functionalityShort form for designers, guidelines for manufactur ers

•Examples:•Motor drive, electricity meter, VAV-controller, etc

LONMARK-Objects

SNVTs

NVs

Quelle: Echelon®

•LONMARK®-Node Objects• Information about the device as a whole

• Mechanism to register the status of the device and its node

• Other L ONMARK®-Objects• Standardised mechanism for communication

behaviour• LONMARK®-Object Types: Sensor, Actuator,

Node Object

LONMARK-Object

LONMARK-Object

Node Object

Data Transfer

interoperableinterface

LONMARK Function Profiles


• LONMARK®-Object Types: Sensor, Actuator,Controller

• Configuration Properties• Device configuration information

• Product documentation• Description of the network interface of the device

• Optional non-interoperable interfaces

• user-defined application interfaces

Produkt documentation

LONMARK-Object

Configuration Properties

Explicit Meldungen

NV

SNVT NVSNVT NV

NVNon-interoperable

interface

Quelle: Echelon®

Network Management Tools

� There are ‚binding tools‘ available to install and set up a LON network.

� Amongst others there are:

� RXT10 (SBT)

� LonMaker (Echelon)


� LonMaker (Echelon)

� NL220 (Newron System)

Network Management Tools

� There is a licence fee for all open tools whcih is demanded by Echelon on installation. This is normally carried out using a dongle or using a licence linked to the computer.

� Using the RXT10 tools the licence fee is not imposed since this is solved by Echelon and SBT in another way.


Topologies

Line Topology

Node Node Node

TERM TERM


Node Node Node

Line topology always needs two bus terminators !

Stub of maximum 3mQAX.

XXXX

QAX.

XXXX

Free Topology

Node Node Node Node

Node

TERM


A bus terminator is always necessary with free topology !

Free topology is possible as a ring Free topology is possible as a ring Free topology is possible as a ring Free topology is possible as a ring

or as a pure staror as a pure staror as a pure staror as a pure starNode

NodeNode

Node

Node

Cable Types

Free Topology Line TopologyTotal Length

Total Length Max. Distance between two nodes

TIA 568A Category 5 ≤≤≤≤ 450m 250m ≤≤≤≤ 900m

Belden 8471 ≤≤≤≤ 500m 400m ≤≤≤≤ 2200m

Belden 85102 ≤≤≤≤ 500m 500m ≤≤≤≤ 2200m


Level IV, 22AWG ≤≤≤≤ 500m 400m ≤≤≤≤ 1150m

JY (St) Y 2x2x0,8 ≤≤≤≤ 500m 320m ≤≤≤≤ 750m

LON A

LON B

For cables not stranded in pairs then always use the opposite channels (EIBFor cables not stranded in pairs then always use the opposite channels (EIBFor cables not stranded in pairs then always use the opposite channels (EIBFor cables not stranded in pairs then always use the opposite channels (EIB----cable)cable)cable)cable)

Corso “DOMOTICA ED EDIFICI INTELLIGENTI” – UNIVERSI TA’ DI URBINODocente: Ing. Luca RomanelliMail: [email protected]


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LonWorks - fine

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Protocolli LonWorks - University of Urbino · node B node C &&& Structure of a Network Variable ......

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