DS200RTBAG2AFB通用電氣模塊
LONWORKS通信將選項(xiàng)板A-1添加到控制器以擴(kuò)展I/O容量。董事會(huì)使用LonWorks通信
通過單雙絞線網(wǎng)絡(luò)與遠(yuǎn)程LonWorks設(shè)備通信的協(xié)議。圖表顯示：選項(xiàng)板添加到MPU控制器板和遠(yuǎn)程安裝的LonWorks節(jié)點(diǎn)。LonWorks遠(yuǎn)程I/O板使用自由拓?fù)涫瞻l(fā)器，以78.1 Kbps通信。
最多可將十五（15）個(gè)物理節(jié)點(diǎn)連接到控制器。
首先將所有節(jié)點(diǎn)連接到網(wǎng)絡(luò)，安裝LonWorks網(wǎng)絡(luò)。下一步，臨時(shí)連接基于PC的使用Echelon公司生產(chǎn)的SLTA（串行鏈路通話適配器）將網(wǎng)絡(luò)管理器連接到網(wǎng)絡(luò)
網(wǎng)絡(luò)管理器（MetaVision 3.0）和SLTA包含在LonWorks啟動(dòng)工具包中。然后，每個(gè)單獨(dú)的節(jié)點(diǎn)由網(wǎng)絡(luò)管理器安裝并保存在項(xiàng)目文件中。項(xiàng)目文件是網(wǎng)絡(luò)安裝的永久記錄，必須保留以備將來進(jìn)行任何網(wǎng)絡(luò)維護(hù)。當(dāng)
首先安裝節(jié)點(diǎn)，網(wǎng)絡(luò)管理器讀取程序ID和神經(jīng)元ID（每個(gè)LonWorks設(shè)備都有包含全球唯一ID的神經(jīng)元芯片）。如果以前沒有具有相同程序ID的節(jié)點(diǎn)安裝后，它將從節(jié)點(diǎn)讀取所有自文檔。網(wǎng)絡(luò)管理器現(xiàn)在將有一個(gè)所有該節(jié)點(diǎn)內(nèi)的可用參數(shù)和I/O變量?？赡苄枰渲媚承﹨?shù)，但對(duì)于對(duì)于大多數(shù)應(yīng)用程序，默認(rèn)設(shè)置是可以接受的。然后使用網(wǎng)絡(luò)管理器綁定網(wǎng)絡(luò)變量（即將i/O變量從一個(gè)節(jié)點(diǎn)連接到另一個(gè)節(jié)點(diǎn)）。
從遠(yuǎn)程節(jié)點(diǎn)到控制器的網(wǎng)絡(luò)變量連接通過以下方式在控制器內(nèi)使用：?jiǎn)蝹€(gè)環(huán)路配置中的LonWorks I/O功能塊12。這些功能塊在本手冊(cè)的“功能塊”部分允許將網(wǎng)絡(luò)變量連接到其他塊控制器內(nèi)的輸入。有許多不同的塊類型可用。塊選擇取決于要連接的變量類型。
西門子支持LonWorks標(biāo)準(zhǔn)網(wǎng)絡(luò)變量類型：
?模擬輸入和輸出的SNVT_lev_percent
?離散輸入和輸出的SNVT_lev_disc
?SNVT_state，用于西門子16通道離散輸入或輸出模塊，固件1.30或更高
每個(gè)網(wǎng)絡(luò)限制有15個(gè)節(jié)點(diǎn)。當(dāng)控制器應(yīng)用程序需要大量I/O計(jì)數(shù)時(shí)，請(qǐng)使用物理
具有較高I/O計(jì)數(shù)的節(jié)點(diǎn)，以最小化所需的物理節(jié)點(diǎn)數(shù)量。例如，西門子提供
16通道離散輸入和輸出模塊。在控制器配置中，每個(gè)控制器最多可使用六個(gè)。A 4-還提供通道模擬輸入模塊和2通道模擬輸出模塊。服務(wù)考慮
LonWorks網(wǎng)絡(luò)的功能可能受到以下因素的影響：
?升級(jí)MPU控制器板固件
?用具有不同固件版本的板替換控制器的MPU控制器板
?將LonWorks板移動(dòng)到具有不同MPU控制器板固件版本的控制器
LONWORKS COMMUNICATIONS
Option board A-1 is added to a controller to expand the I/O capacity. The board uses the LonWorks communication
protocol to communicate with remote LonWorks devices over a single twisted pair network. The diagram shows
the option board added to an MPU Controller board and remote mounted LonWorks nodes.
A LonWorks Remote I/O board uses a Free Topology transceiver communicating at 78.1 Kbps.
Up to fifteen (15) physical nodes can be connected to a controller.
Install a LonWorks network by first wiring all the nodes to the network. Next, temporarily connect a PC-based
Network Manager to the network using a SLTA (Serial Link Talk Adapter) manufactured by Echelon Corp. The
Network Manager (MetaVision 3.0) and the SLTA are included in the LonWorks Startup Kit.
Each individual node is then installed by the Network Manager and saved in a Project file. The Project file is a
permanent record of the network installation and must be retained for any future network maintenance. When a
node is first installed, the Network Manager reads the Program ID and the Neuron ID (every LonWorks device has
a Neuron chip that contains a worldwide unique ID). If a node with the same Program ID had not been previously
installed, it will read all of the self-documentation from the node. The Network Manager will now have a list of all
the available parameters and I/O variables within that node. Some parameters may need to be configured, but for
most applications, the default settings are acceptable. The Network Manager is then used to BIND network
variables (i.e. connect I/O variables from one node to another).
Network variable connections from remote nodes to the controller are used within the controller by selecting
LonWorks I/O function blocks within individual loop configurations12. These function blocks, which are detailed in
the Function Blocks section of this manual, enable connections to network variables to be made to other block
inputs within the controller. There are a number of different block types available. Block selection depends on the
types of variables to be connected. Siemens supports LonWorks Standard Network Variable Types:
? SNVT_lev_percent for analog inputs and outputs
? SNVT_lev_disc for discrete inputs and outputs
? SNVT_state for use with the Siemens 16-channel discrete input or output modules available with firmware 1.30
or higher
There is a 15 node per network limit. When large I/O counts are needed for a controller application, use physical
nodes with higher I/O counts to minimize the number of physical nodes required. For example, Siemens provides
16-channel discrete input and output modules. Up to six of each can be used within a controller configuration. A 4-
channel analog input module and a 2-channel analog output module are also available. SERVICING CONSIDERATIONS
The functioning of a LonWorks network can be affected by:
? Upgrading the MPU Controller board firmware
? Replacing a controller’s MPU Controller board with a board having a different firmware version
? Moving a LonWorks board to a controller with a different MPU Controller board firmware version
