GE P485 instruction manual Sub-network data flow

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SOFTWARE OVERVIEW

SUB-NETWORKThe second step in the configuration wizard selects the properties for the Modbus sub- PROPERTIES network. The data flow for the sub-network is shown below.

Fieldbus

Master

Fieldbus

Data Direction

In

Out

GE

Converter

Modbus

Sub-Network

Figure 4-2: Sub-network data flow

Refer to the particular sub-network device manual(s) to determine the appropriate settings and communication options. If multiple devices are being installed on the same sub- network, they must be configurable for a common set of communication parameters.

All numerical values are entered and shown in decimal unless otherwise specified.

The sub-network properties window is shown below.

NOTE

•Physical standard: The physical standard can be either RS232, RS485, or RS422.

RS232 is a point-to-point communication standard; that is, it is only possible to have one sub-network node (Modbus device) connected to the P485 converter when using RS232. RS232 supports a maximum cable length of 15 meters and is full duplex. It uses two signal lines (Rx and Tx) and the signal is measured relative to ground.

RS485 is a common multi-drop communication standard. It is used with larger cable distances with one or several sub-network nodes (Modbus devices) connected. RS485 supports a maximum of 31 nodes, with half duplex and a total cable length up to 1200 meters. It uses two signal lines (A-line and B-line, twisted pair) with the signal being measured between the two lines.

RS422 is a common multi-drop communication standard. It is used with larger cable distances with one or several sub-network nodes connected. RS422 supports a maximum of 31 nodes, with full duplex and a total cable length up to 1200 meters. It uses four signal lines (receive A1-B1 and transmit A2-B2, twisted pair) with the signals being measured between the two signal lines A and B.

•Bitrate (bits/s): This parameters refers to the speed of the sub-network. Speeds are 1200 to 57600 bps in predefined steps. The bitrate is also referred to as baud rate.

4–4	P485 MODBUS TO PROFIBUS CONVERTER – USER GUIDE

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Contents P485 Modbus to Profibus Converter GE MultilinPage Table of contents P485 Modbus to Profibus ConverterSoftware Frame Miscellaneous Introduction Getting startedDocument conventions Input and output definitionAbout the P485 Modbus to Profibus Converter FeaturesFeatures Ordering SpecificationsMechanical Housing CommunicationsElectrical installation InstallationQuick install Profibus connector pin assignments Pin Signal DescriptionConfiguration cable pin assignments P485 end Pin DescriptionConfiguration cable PC end Mechanical installation Indicators and switchesP485 status indicators Number Description State StatusProfibus installation procedure Input/output bytes required ModulesTroubleshooting Poor performanceData exchange OverviewAddress Contents Access Memory MapProtocol configuration BlocksData Exchange Introduction Installation procedureSoftware overview Using the EnerVista P485/D485 Setup software Select Configuration Wizard and click on OKTypical network arrangement Sub-network data flow Address Command Software Overview P485 Modbus to Profibus Converter User Guide Software Overview Configuration main window Configurator main windowInformation window Fieldbus configuration Function DescriptionP485/D485 configuration P485/D485 configurationModbus network configuration Parameter Description RangeSoftware Overview Communication model PLCBasic settings P485 scan listNodes MenuCommunication Model P485 Modbus to Profibus Converter User Guide Communication Model Frame and command editors Frame editorCommand editor Select command windowSelect ‘Add Command’ as described earlier Query ColumnMain window Modbus network and node monitors Modbus network monitorStart / Stop sub network scanning Update OFF Update on Node monitorCommand Area Advanced functions Control and status registersBits Name Description Code Name DescriptionCode Error Description Handshake bits themselves bits 14Input/output data during startup Fieldbus control systemAdvanced fieldbus configuration Mailbox commandAdvanced Functions Application example OverviewFor the MM2, we have Type Parameter Address Format Read/writeModbus user map setup Parameter User map data AddressMM2 meter user map setting System configuration System configurationSetup Software Starting Configuration Wizard DB9 pin DescriptionSelecting the SUB-NETWORK Properties Modbus network propertiesParameters configured for Pqmii Connect Devices to the SUB- Network 11 Connect devices to sub-networkSelect Parameters for Each Node 14 Select parameter window17 Configuration report 20 Save device file Queries21 Expanding the tree 23 Changing configuration parameters for a query 25 Opening a saved configuration file Profibus network setup Revision history WarrantyMiscellaneous Release Dates10-2 P485 Modbus to Profibus Converter Index 6-3Power Supply