Honeywell XYR 5000 LINE manual Terminating Communications Wiring to the Base Radio

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Figure 3-8 Daisy-Chaining RS-485 to Multiple Base Radios

3.2.7 Terminating Communications Wiring to the Base Radio

RS-485 is capable of maintaining communications over a maximum distance of 4000 feet. In most (and we recommend all) situations the unit that comprises an “end” of an RS-485 network should be terminated by a resistor wired across the A and B wires.

In the case of a daisy-chained application the end unit should be terminated. The end unit is the unit that is located at the end of the series of units. In a PC to Base Radio only application, the end unit is the Base Radio. Note: a PC is also an end unit, but the termination for this end unit is done within the converter. In a multiple unit daisy-chain application the end unit is shown in Figure 3-9.

Figure 3-9 Example of End Unit in Daisy-Chain Configuration

Termination of an end unit is done by placing a resistor across the A and B wires of the RS-485 cable. The value of this resistor should match the characteristic impedance (Zo) of the RS-485 cable. The characteristic impedance (Zo) is published by the manufacturer of the RS-485 cable you are using. If you are using the Belden RS-485 wire

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Contents XYR 5000 Line 34-XY-25-05 Rev 08/06 Base Radio User GuidePage FCC Certification Base RadioRevision Notes ContactsTelephone Table of Contents Quare R OOT F Unction Table of Figures Overall Wiring SchematicUsing this Manual IntroductionAbout the Device Software Compatibility UnpackingQuick Start Overall Wiring SchematicPage Installation Mechanical InstallationBase Radio Positioning General Layout Electrical Specifications Electrical InstallationTerminal Block Labels Wiring RS-485 to the Base Radio Wiring Power to the Base RadioWiring RS-485 to the Base Radio Wiring the RS-485/232 Converter to the Base RadioUSB Driver Installation Wiring the RS-485/USB Converter to the Base RadioWiring the DB-9 RS-485 Cable to the Base Radio Daisy-Chaining Multiple Base Radios to Single RS-485/PowerUSB Converter’s Male DB-9 Connector USB Driver Un-installationDaisy-Chaining RS-485 to Multiple Base Radios Daisy-Chaining Power to Multiple Base RadiosDaisy-Chaining RS-485 to Multiple Base Radios Terminating Communications Wiring to the Base RadioHigh Gain Antenna Grounding the Base RadioGeneral Configuration Base Radio Displayed MessagesRead Only Sequence Read Only Sequence Overall Configuration Menu MapMenu Map to Password Setting Setting the User PasswordRF Channel Selection Configuring the RF CommunicationsRF Baud Rate Selection Menu Map to RF Baud Rate SettingHigh Rfid Setting High RF ID SettingModbus Baud Rate Setting Base Radio SetupMenu Map to Modbus Baud Rate Setting Modbus Device ID SettingPage Modbus Mapping Mode Setting Modbus Parity SettingRegmode Modbus Communication ProtocolModbus Commands Command 03-Read Holding RegistersCommand 08- Diagnostic Command 11- Get Com Event Counter Command 12- Get Com Event LogCommand 17- Report Slave ID Base Radio Holding Registers Command 43- Read Device IDRegister Address Description Register Type Register Address DescriptionBase Radio Device Status Registers Base Radio Device Type RegistersBase Radio On/Offline Transmitter Registers Value Base Radio Device StatusRegister Mapping Mode Device ID Mapping ModeTransmitter Holding Registers Register AddressValue Device Type Transmitter Device Type Holding RegistersSquare Root Function Alarm Condition WN571 onlyTransmitter Device Status Registers Value Transmitter Device StatusTechnical Specifications Overall Base Radio Dimensions Appendix a Navigating the Menus Figure A- 1 Base Radio Menu Map Appendix B Base Radio Menu MapAppendix C Modbus Register Definitions Page Page Page Honeywell