Protocolli LonWorks
Transcription
Protocolli LonWorks
Corso “DOMOTICA ED EDIFICI INTELLIGENTI” – UNIVERSITA’ DI URBINO Docente: Ing. Luca Romanelli Mail: romanelli@baxsrl.com Protocolli LonWorks Domotica ed edifici intelligenti – Università di Urbino 1 Concept Definitions LON Echelon LONWORKS LONWORKS Protocol LONMARK Node Neuron SNVT SCPT LNS XIF-File - Local Operating Network - Inventors of the technology - Collective term for the technology - Communication protocol - 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 Domotica ed edifici intelligenti – Università di Urbino 2 What is LONWORKS® Technology? -LON (Local Operating Network) is a decentralised control network for building automation, in industry, in transport, in telecommunications and in many other areas. -The communication of intelligent sensors, actuators and operator units of a LON® network is the result of a protocol already implemented in the Neuron®-Chip, this is the LonTalk® protocol. Domotica ed edifici intelligenti – Università di Urbino 3 Philosophy of LONWORKS® Networks 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. 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. Domotica ed edifici intelligenti – Università di Urbino 4 InformationInformation-based System Motion Room occupied Brightness Feedback Temperature Setpoint Setpoint 21°C 0%-100% The sensors in a LonWorks network make their information available. Actuators process this information as required. Domotica ed edifici intelligenti – Università di Urbino 5 InformationInformation-based System Motion Room occupied Brightness Feedback Temperature Setpoint Setpoint 21°C 0%-100% The allocation of the individual network variables is established using a soso-called Binding. Domotica ed edifici intelligenti – Università di Urbino 6 InformationInformation-based System Motion Room occupied Brightness Feedback Temperature Setpoint Setpoint 21°C 0%-100% Intruder Key Code Aktive / inaktive Function enhancement is implemented in newly added devices. Therefore interruption of the remaining functions when extending a network is mostly not necessary. Domotica ed edifici intelligenti – Università di Urbino 7 Bindings are in no way intelligent ! node A Logical functionality must always be realised in the actuator node C node B & Domotica ed edifici intelligenti – Università di Urbino 8 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 Name NV Type nvoOutsideTemp SNVT_temp_p Domotica ed edifici intelligenti – Università di Urbino 9 Connection between network variables Network variables behave like coded plugs SNVT_temp_p SNVT_temp_p SNVT_temp SNVT_temp SNVT_temp X SNVT_temp_p Domotica ed edifici intelligenti – Università di Urbino 10 Network Variables Generally there are two different types of network variables: SNVT = Standard Network Variable Type UNVT = User-defined Network Variable Type Domotica ed edifici intelligenti – Università di Urbino 11 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 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. Domotica ed edifici intelligenti – Università di Urbino 12 Options for Message Services Unacknowledged Unacknowledged sending of messages on the network. Unacknowledged Repeated 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. Domotica ed edifici intelligenti – Università di Urbino 13 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, ....) Domotica ed edifici intelligenti – Università di Urbino 14 Node Addresses Neuron ID Each 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 Addresses Each 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 Domain ID Subnet 1 Node 1 Subnet 255 Node 127 Node 1 Subnet ID Node 127 Node ID Domotica ed edifici intelligenti – Università di Urbino 15 Types of Addresses LON communication mainly uses the following methods of addressing: Subnet / Node Adressing normally used when a node speaks directly to another node. Group Adressing normally used when a node speaks simultaneously to more than one node. Broadcast Adressing used 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. Domotica ed edifici intelligenti – Università di Urbino 16 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! Domotica ed edifici intelligenti – Università di Urbino 17 Transceiver Devices in LON networks have different transceivers, some of this are: FTT-10A Transmitter for LON node with its own voltage supply. LPT-10 Transmitter for LON node which obtains its voltage supply from the LON bus. Use of both types of transceivers is allowed. Domotica ed edifici intelligenti – Università di Urbino 18 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 but the load on the bus. If the number of permissible nodes in the segment is exceeded then extra infrastructure components are needed. Domotica ed edifici intelligenti – Università di Urbino 19 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. Domotica ed edifici intelligenti – Università di Urbino 20 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 Physical repeaters repeat everything – even disturbances !!! Domotica ed edifici intelligenti – Università di Urbino 21 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 Domotica ed edifici intelligenti – Università di Urbino 22 Router 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. 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 Domotica ed edifici intelligenti – Università di Urbino 23 LON Proxy Node 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 possible Simple mapping of the required network variables using external configuration files Dynamic network interface Extra properties such as active polling, or extension of the Neuron-Chip limitations using addressing Domotica ed edifici intelligenti – Università di Urbino 24 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) Domotica ed edifici intelligenti – Università di Urbino 25 Network Interface For Laptops there is an array of other network cards: PCC10 (Echelon) PCMCIA Card Attention : this card does not function with all Laptops! 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. Domotica ed edifici intelligenti – Università di Urbino 26 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. Domotica ed edifici intelligenti – Università di Urbino 27 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 Domotica ed edifici intelligenti – Università di Urbino 28 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, 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. Domotica ed edifici intelligenti – Università di Urbino 29 SNVT Master List Domotica ed edifici intelligenti – Università di Urbino 30 SNVT Master List SNVT_switch No.95 state value 0 .. 100% Values according toTable Percent resolution 0,5% Value Command Remark 0 OFF Command Off 1 ON Command On ZERO Inactive 0xFF Structure 2 byte Domotica ed edifici intelligenti – Università di Urbino 31 SNVT Master List SNVT_temp_p Nr.105 value -273,17 .. 327,66°C Temperature Resolution 0,01°C Signed_long 2 byte Domotica ed edifici intelligenti – Università di Urbino 32 SNVT Master List SNVT_setting Nr.117 function setting rotation 0 .. 100% Listing -359.98 .. 360.00 Grad Angle resolution 0.02 degrees Positioning Value Structure 4 byte Command Remarks 0 SET_OFF Command Off 1 SET_ON Command On 2 SET_DOWN Command Down 3 SET_UP Command Up 4 SET_STOP Stop 5 SET_STATE Positon to a value SET_NUL Inactive 0xFF Domotica ed edifici intelligenti – Università di Urbino 33 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 differently. In the past this often happened with applications concerning blinds. This demands caution when working on existing projects. Domotica ed edifici intelligenti – Università di Urbino 34 Interoperability Example: Blinds 0% - 90% node 0% 180% 90% A node snvt setting 90% B The value of the angle of the blind can be interpreted differently by different manufacturers snvt setting Domotica ed edifici intelligenti – Università di Urbino 35 LONMARK Objects Sensor, Control Object Type Nr. 2 nv1 nviValueFb SNVT_xxx nv2 nv3 nviPresetFb SNVT_preset nv5 nvoValue SNVT_xxx nvoPreset SNVT_preset nc17 – Location Description nc31 – Amplification Factor nc26 - Offset nc20 - max. Range nc23 - min. Range nc27 – for sending Delta nc22 - max. Sending Time nc24 - min. Sending Time nc16 – Invert Output nc28 – Conversion Table X etc. Domotica ed edifici intelligenti – Università di Urbino 36 Configuration Properties 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#): applying configuration properties the (limited) number of network variables which can be declared on a node is not 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!) Domotica ed edifici intelligenti – Università di Urbino 37 LONMARK Function Profiles • LONMARK®-Objects • Pre-defined software templates which can be used to describe the device behaviour. •For Communication Network Variables SNVTS •For Installation pre-defined Format for self-documentation •For Optimization pre-defined format for the definition and calibration of configuration parameters •Function Profiles A collection of LONMARK® Objects Common method to define clearly functionality Short form for designers, guidelines for manufacturers •Examples: •Motor drive, electricity meter, VAV-controller, etc Device Function Profile LONMARKObjects SNVTs NVs Quelle: Echelon® Domotica ed edifici intelligenti – Università di Urbino 38 LONMARK Function Profiles •LONMARK®-Node Objects Node Node Object Object • Information about the device as a whole Data Transfer • Mechanism to register the status of the device and its node LONMARKObject • Other LONMARK®-Objects interoperable interface LONMARKObject LONMARKObject • Device configuration information Produkt documentation NV • Product documentation SNVT NV NV Explicit Meldungen behaviour • LONMARK®-Object Types: Sensor, Actuator, Controller • Configuration Properties Configuration Properties SNVT NV • Standardised mechanism for communication Non-interoperable interface • Description of the network interface of the device • Optional non-interoperable interfaces • user-defined application interfaces Quelle: Echelon® Domotica ed edifici intelligenti – Università di Urbino 39 Network Management Tools There are ‚binding tools‘ available to install and set up a LON network. Amongst others there are: RXT10 (SBT) LonMaker (Echelon) NL220 (Newron System) Domotica ed edifici intelligenti – Università di Urbino 40 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. Domotica ed edifici intelligenti – Università di Urbino 41 Topologies Line Topology Node Node Node TERM TERM Node Node Node X Stub of maximum 3m QAX. Line topology always needs two bus terminators ! Domotica ed edifici intelligenti – Università di Urbino 43 Free Topology Node Node Node Node X Node QAX. TERM Node Node Node Node Node Free topology is possible as a ring or as a pure star A bus terminator is always necessary with free topology ! Domotica ed edifici intelligenti – Università di Urbino 44 Cable Types Free Topology Line Topology Total 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 (EIB(EIB-cable) Domotica ed edifici intelligenti – Università di Urbino 45 Corso “DOMOTICA ED EDIFICI INTELLIGENTI” – UNIVERSITA’ DI URBINO Docente: Ing. Luca Romanelli Mail: romanelli@baxsrl.com Protocolli LonWorks - fine Domotica ed edifici intelligenti – Università di Urbino 46