Transcript SLC 500 Communications
SLC 500 Communications
SLC 500 COMMUNICATIONS
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SLC 500 Communications
Requirements for Industrial Networks
An industrial communication link
Capable of supporting real-time control
High data integrity
High noise immunity
High reliability in harsh environments
Suitable for large installations
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SLC 500 Communications
Local Area Network - Applications
Centralized Data Monitering and Acquisition
Manufacturing
SCADA
MMI Distributed Control
Communication between programmable controllers
Upload to a programmer or host computer from any PLC
Download from a programmer or host computer to any PLC
Read/write I/O values, registers of any PLC
Monitoring of PLC status and control of PLC operation
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SLC
SLC 500 Communications
Network Topologies
Daisy-Chain
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Each device has two sections of cable tied together
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Each end has termination (resistor/capacitor) Examples DH+ DH-485 Remote I/O Beldon #9463 cable
SLC SLC SLC 4
SLC 500 Communications
Network Topologies
Star
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All devices physically connected at one point Example Ethernet
PLC PLC PLC PLC 5
SLC 500 Communications
Network Topologies
Trunk-Line / Drop-Line
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Trunk line very long - run through plant
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Drop lines very short Drops connected to trunk with Y-adapters Examples Data Highway (DH) Devicenet DH+ can be Trunk Line Drop Line
SLC
Drop Line Drop Line
SLC SLC
Drop Line
SLC 6
TOKEN
# 1
SLC
SLC 500 Communications
Network Access Methods
Token Passing:
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Each node can talk on the network when it
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has the token After done talking, the node will “Pass the token” to the next node Multi-master network Eliminates data collisions # 2
SLC
# 3
SLC
# 4
SLC 7
Network Controller (Master) Request ?
SLC 500 Communications
Network Access Methods
Master / Slave:
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Master talks to one slave at a time
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The slave can only talk if the master
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asks it for some information Polling network Eliminates data collision Single master network # 1
SLC (Slave) Reply !
# 2
SLC (Slave)
# 3
SLC (Slave)
# 4
SLC (Slave) 8
SLC 500 Communications
Networks - How to Decide on One?
Maximum number of devices
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How many nodes are required for the application?
How many nodes should be reserved for future expansion?
Maximum network length
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Usually specified as the physical cable distance from the first node to the last node on the network
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Drop length is the length of cable from the main cable to the node Device supported
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Programmable controllers Programming devices Operator Interfaces Other Computers - PCs, Workstations, Minis, Mainframes...
Response time
Application interface
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SLC 500 Communications
A-B Communication Network Terms
RS-232 RS-422 RS-485 DH-485 REMOTE I/O DF1 DH+ What the hell do all these mean?
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SLC 500 Communications
A-B Communication Network Terms
RS-232 RS-422 RS-485 Electrical Connections
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DH-485 DF1 DH+ REMOTE I/O
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Protocols (languages) Must have matching electrical connections and protocols for two computers to communicate.
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SLC 500 Communications
Communications - Like a Phone Call...
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SLC 500 Communications
Communications - Like a Phone Call...
Electrical Connection is made when person answers phone
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SLC 500 Communications
Communications - Like a Phone Call...
Electrical Connection is made when person answers phone ENGLISH COMMS FRENCH
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SLC 500 Communications
Communications - Like a Phone Call...
Electrical Connection is made when person answers phone Communication when connection make AND both people speak the same language ENGLISH ENGLISH COMMS FRENCH COMMS ENGLISH
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SLC 500 Communications
Networks: DH-485 and DH+
Network Communications
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Program support and monitering
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Supervisory control for distributed hierarchy
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Operator interface for monitoring and control
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SLC 500 Communications
DH-485 Characteristics
DH-485 Multi-drop link
Daisy chain configuration
Token passing system
9.6 or 19.2 Kbaud data rate
Connect up to 32 devices on network
Up to 4000 cable feet (1200 meters) of network lenght
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SLC 500 Communications
DH485 Peer-to-peer Comms.
Send/Recv messages from other SLC 500s
Multi-master token-passing ring; 32 nodes
5/02, 5/03 + 5/04 can initiate communications to other processors
5/03 can using Channel 0, Channel 1, or both
5/04 can using Channel 0 only
Fixed and 5/01 respond only
Initiate comms. with MESSAGE instruction in ladder logic
NO ladder programming necessary to respond to a message from another processor
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SLC 500 Communications
Typical DH-485 Network
ALLEN-BRADLEY RUN DTAM Plus ALARM PIC
AIC+ Link Coupler Link Coupler Link Coupler Link Coupler SLC 5/04 SLC 5/01 SLC 500 Fixed SLC 5/03 SLC 5/02 19
SLC 500 Communications
DH+ Characteristics
• • • • • • •
Peer-to-Peer Communication
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Utilizes Tolken Passing 64 nodes maximum Remote Programming of SLC 500’S, PLC-2, PLC 3, and PLC-5 Direct Connections to 5/04,PLC-5, Panelview, and Industrial Terminals 57.6, 115.2, OR 230Kbaud data rate Pub # 1770-6.5.16 DH/DH-485/DH+ Ref Manual Robust Industrial Network
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SLC 500 Communications
DH+ Communications
SLC-5/04 DH+ RSLogix 500 Software AI 500 Software 6200/AI Software 57.6Kbaud: 10,000 feet 115.2Kbaud: 5,000 feet 230.4Kbaud: 2,500 feet PLC-5 Other Processors PLC-2, PLC-3 PLC-5/250 21
SLC 5/04
SLC 500 Communications
DH+ to DH-485 Interface
Interface through a 1785-KA5
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Translate DH-485 <-> DH+ Allows PLC5s and SLCs to communicate
RSLogix 500 Software PLC-5 PLC-5 DH+ DH-485 Network #1 Link Coupler Link Coupler DH+ DH-485 Network #2 Link Coupler Link Coupler SLC 5/01 SLC 5/02 SLC 5/03 SLC 5/03 22
SLC 500 Communications
RS-232 Communications
SLC-5/03 and 5/04 Support:
Full-Duplex (Point-to-Point)
Half- Duplex
ASCII
Modem Communication
SLC 500 Communications
RS-232: DF1 Full-Duplex
AKA: DF1 Point-to-Point
Simultaneous transmission between two devices in both directions - Programming Port - Peer Messaging
SLC 500 Communications
RS-232: DF1 Half-Duplex
Mulit-Drop, Single Master, Multiple Slave
Slaves are Polled for Response from the Master
Supports up to 255 Slave Devices
Slaves: Any SLC Processor
Master: PLC-5, SLC-5/03, 5/04, CV
SLC 500 Communications
5/03 + 5/04 Serial Port
Point-to-point communications
RS-232
Using Channel 0 w/ DF1 Full-Duplex
RSLogix 500 Programming Software Modem Modem SLC 5/03 or 5/04 26
SLC 500 Communications
5/03 + 5/04 Serial Port
Master/Slave communications
Polled Network
Using Channel 0 w/ DF1 Half duplex Master or Slave Master
DF1 Master (RSView) Modem
Slave(s)
Modem Modem Modem SLC 5/04 27 RSLogix 500 Programming Software SLC 5/03
SLC 500 Communications
ASCII Communications
5/03 and 5/04
Direct connection to devices such as barcode decoders and printers
Eliminates requirement of BASIC module for this task
SLC 5/03 CPU RUN FORCE FLT DH485 BATT RUN REM RS232 PROG 28
SLC 500 Communications RS-232
DH-485 / RS-232 ACT 485 CFG DF1 FAULT BA LOW H/D F/D
1747-KE Module
Converts electrical signals
– RS-485 to RS-232
Translates protocols
– DH-485 to DF1
Configured thru the backplane (Series B) Config RS-232 DF1 RS-485 DH-485
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SLC 500 Communications
1747-KE Module
RS-485/DH-485 to RS-232C/DF1 interface module Acts as a BRIDGE between two different networks or types of communication Called a Bridge module (1) DH-485 port (2) Serial ports (RS-232, 422, 485) Allows remote communications to SLC 500 systems
DH-485 / RS-232 ACT 485 CFG DF1 FAULT BA LOW H/D F/D 30
Modem Modem SLC 500 CPU with KE module
SLC 500 Communications
Typical KE Configurations
RSLogix 500 SLC 500 • Point-to-Point configuration using full duplex DF1 communications • Remote communications from the programming software to a remote network of SLC 500 processors.
• RSLogix 500 acts as if it were directly on the DH-485 network DH-485 Isolated Link Coupler 1747-AIC SLC 5/01 31
SLC 500 Communications
Typical KE Configurations
Master
Master/Slave communications
Polled Network
Using Channel 0 w/ DF1 Half duplex Slave Slave(s)
Modem Modem Modem DF1 Master (RSView) Modem Modem RSLogix 500 Programming Software SLC 500 with KE SLC 5/02 with KE SLC 5/01 with KE 32
SLC 500 Communications
Peer-to-Peer Communications
Read/Write: Read - local processor is receiving data Write - local processor is sending data Target Device: 500CPU if target is another SLC Processor 485CIF if target is a non-SLC device on the network PLC5 if target device accepts PLC-5 commands Local/Remote: Local - the message is to be communicated via a local network Remote - the message is to be communicated to a remote device on another network through a bridge Control Block: Contains - target node address, local file address, target file address, status bits MSG Control Block Length: Fixed at 14 elements Setup Screen: Advanced setup parameters EN: enable bit - set when rung is true DN: done bit - message successfully transmitted ER: error bit - transmission failed Read/Write Message Type Peer-To-Peer Read/Write Read Target Device 500CPU Local/Remote Local Control Block ? Control Block Length 14 Setup Screen ( EN ) ( DN ) ( ER ) 33