Omega Speaker Systems iLD Series manual Wiring RS485 Interface, Device # with RS485

Page 11

2.4.1 Wiring RS485 Interface

RS485 interface uses a two-wire communication system (one for transmitting and one for receiving) plus a common wire to connect to the shield of the cable. It is recommended to use a shielded cable with one twisted pair.

Use of twisted pair and shield will significantly improve noise immunity.

Figure 2.3 shows multi-point, half-duplex RS485 interface connections for the iServer.

iLD Big Display TB4	DEVICE #1
iLD Big Display TB4	-Tx/-Rx	+Tx/+Rx
1 2 3	-Tx/-Rx	+Tx/+Rx	GND
1 2 3			.........................
-Tx/-Rx
+Tx/+Rx

Twisted shielded pair

...............................

-Tx/-Rx

+Tx/+Rx

GND

DEVICE #29

-Tx/-Rx

+Tx/+Rx

GND

DEVICE #31

-Tx/-Rx

+Tx/+Rx

GND

120 Ohm

Termination resistor

-Tx/-Rx +Tx/+Rx GND

...............................

DEVICE #2

DEVICE #30

Figure 2.3 Multi-point, Half-Duplex RS485 Wiring

Value of the termination resistor is not critical and depends on the cable impedance.

Table 2.3 shows RS485 half-duplex hookup between the iServer serial port and device with RS485 communication interface.

Table 2.3 Half Duplex Hookup

TB4 Pin#	iLD Big Display	DEVICE # WITH RS485
Pin 2	+Tx/+Rx (+Transmit/+Receive)	+Tx/+Rx (+Transmit/+Receive)
Pin 3	-Tx/-Rx (-Transmit/-Receive)	-Tx/-Rx (-Transmit/-Receive)
Pin 1	RTN (Common GND)	GND (Common GND)

7

Image 11

Contents User’s Guide Servicing North America OMEGAnet On-Line Service Internet e-mail Info@omega.comTable of Contents List of Tables Rear Panel View of i16 and i8 Series Meters withManuals, Software Customer ServiceBefore You Begin Inspecting Your Shipment EMC Considerations Safety and EMC ConsiderationsPart Introduction IServer on the Ethernet Network TB4 Physical Characteristics and MountingPart Hardware Network Communication Interface Section DIP Switches on the iServerSerial Communication Interfaces For Models with RS485 Port Data Transmission Characteristics RS485Device # with RS485 Wiring RS485 InterfaceHalf Duplex Hookup TB4 Pin# ILD Big Display Network Communication Interfaces 1 10Base-T RJ-45 Pinout RJ45 Pinout 2 10Base-T Crossover WiringEthernet MAC Address Part Network ConfigurationNetwork Protocols Dhcp DIP Switch on the iServer DNSPort Number Default IP AddressIP Address Part Operations Command Prefix Command Class MeaningLSB MSB Pinging eis03ec MS-DOS Prompt IServer Home Page Menu Device TypeRead Devices Device Setpoints Read DevicesDevice Setup Modify Device Parameters or Device List Entry Device Setup10 Configuration Serial Communication ConfigurationTerminal Server Device No. Refer to Section 11 Access Control Access Control3 4 OFF Access Control Host Name Refer to .4, DNS12 Access Control Setting a New IP Address over the NetworkTerminal Server Function 13 Terminal Server Configuration14 Terminal Emulation Terminal EmulationTera Term Telnet Connection Screen Telnet Setup17 Telnet Setup iServer Help 01X01074.3 Httpget Program\iServer\Httpget\httpget -r -S *01X01\r ARP Protocol 18 ARP Commands and Responses19 PC-to-Device Communication Remote Access TunnelingRemote iServer 21 Configuration Menu Remote iServerUnder Terminal Server section, set Number of Connections to Local iServerMail Notifier Software InstallationEmail Connection Mapi Access Program Options Setup and Configuration25 iServer Mail Notifier Device Setting Device Setting and Configuration Device setup requiresInternal WEB Server Part Specifications Serial InterfaceNetwork Interface Processor CPUSerial Interface Network InterfaceAppendix a Glossary Appendix B IP Address Class C Appendix C IP NetmaskMask Dotted Notation Mask Binary Mask Bits Class a Class BDec Hex Binary Char No Parity No parity Appendix D Ascii ChartAscii Dec Hex BinaryDec Hex Ctrl Key Definition Char Equiv Appendix D Ascii Chart ContinuationAscii Control Codes Dec Hex Ctrl Key DefinitionPart Approvals Information CE Approvals Information WARRANTY/DISCLAIMER Shop on line at omega.com