1. SLC 500
COMMUNICATIONS 1

2. 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 2

3. 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 3

4. Network Topologies Daisy-Chain Examples
Each device has two sections of cable tied together
Each end has termination (resistor/capacitor)
Examples
DH+
DH-485
Remote I/O
Beldon #9463 cable
SLC 4

5. Network Topologies Star Example
All devices physically connected at one point
Example
Ethernet
PLC
PLC
PLC
PLC 5

6. Network Topologies Trunk-Line / Drop-Line Examples
Trunk line very long - run through plant
Drop lines very short
Drops connected to trunk with Y-adapters
Examples
Data Highway (DH)
Devicenet
DH+ can be
SLC
Trunk Line
Drop Line 6

7. Network Access Methods
Token Passing:
Each node can talk on the network when it has the token
After done talking, the node will “Pass the token” to the next node
Multi-master network
Eliminates data collisions
TOKEN
SLC
# 1
# 2
# 3
# 4 7

8. Network Access Methods
Master / Slave:
Master talks to one slave at a time
The slave can only talk if the master asks it for some information
Polling network
Eliminates data collision
Single master network
Network
Controller
(Master)
Request ?
Reply !
# 1
# 2
# 3
# 4
SLC
(Slave)
SLC
(Slave)
SLC
(Slave)
SLC
(Slave) 8

9. Networks - How to Decide on One?
Maximum number of devices
How many nodes are required for the application?
How many nodes should be reserved for future expansion?
Maximum network length
Usually specified as the physical cable distance from the first node to the last node on the network
Drop length is the length of cable from the main cable to the node
Device supported
Programmable controllers
Programming devices
Operator Interfaces
Other Computers - PCs, Workstations, Minis, Mainframes...
Response time
Application interface 9

10. A-B Communication Network Terms
What the hell do
all these mean?
RS-232
RS-422
RS-485
DH-485
REMOTE I/O
DF1
DH+ 10

11. A-B Communication Network Terms}
RS-232
RS-422
Electrical Connections
RS-485 }
DH-485
REMOTE I/O
Protocols (languages)
DF1
DH+
Must have matching electrical connections and protocols for two computers to communicate. 11

12. Communications - Like a Phone Call...12

13. Communications - Like a Phone Call...
Electrical Connection is made when person answers phone 13

14. Communications - Like a Phone Call...
Electrical Connection is made when person answers phone
COMMS
ENGLISH
FRENCH 14

15. Communications - Like a Phone Call...
Electrical Connection is made when person answers phone
COMMS
Communication when connection make AND both people speak the same language
ENGLISH
FRENCH
ENGLISH
COMMS
ENGLISH 15

16. Networks: DH-485 and DH+ Network Communications
Program support and monitering
Supervisory control for distributed hierarchy
Operator interface for monitoring and control 16

17. 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 17

18. 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 18

19. Typical DH-485 Network Link Coupler SLC 5/03 SLC 5/02 SLC 5/01
SLC 500 Fixed
PIC
ALLEN-BRADLEY
DTAM Plus
RUN
ALARM
AIC+
SLC 5/04 19

20. DH+ Characteristics Peer-to-Peer Communication 64 nodes maximum
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 # DH/DH-485/DH+ Ref Manual
Robust Industrial Network

21. DH+ Communications DH+ Other Processors RSLogix 500 Software
AI 500 Software
6200/AI Software
57.6Kbaud: 10,000 feet
115.2Kbaud: 5,000 feet
230.4Kbaud: 2,500 feet
DH+
Other
Processors
SLC-5/04
PLC-5
PLC-2, PLC-3
PLC-5/250

22. DH+ to DH-485 Interface Interface through a 1785-KA5
Translate DH-485 <-> DH+
Allows PLC5s and SLCs to communicate
RSLogix 500
Software
Link Coupler
SLC 5/01
SLC 5/03
SLC 5/02
PLC-5
DH-485 Network #1
DH-485 Network #2
DH+
SLC 5/04

23. RS-232 Communications SLC-5/03 and 5/04 Support:
Full-Duplex (Point-to-Point)
Half- Duplex
ASCII
Modem Communication
Did we advise non US manufacturing & repair operations?

24. RS-232: DF1 Full-Duplex AKA: DF1 Point-to-Point
Simultaneous transmission between two devices in both directions
- Programming Port
- Peer Messaging
Did we advise non US manufacturing & repair operations?

25. 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
Did we advise non US manufacturing & repair operations?

26. 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 20

27. 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
RSLogix 500 Programming Software
SLC 5/03
SLC 5/04 21

28. 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
PROG
SLC 5/03 CPU
RUN
FLT
BATT
FORCE
RS232
DH485
REM 22

29. 1747-KE Module Config DF1 DH-485 RS-232 RS-232 RS-485
Converts electrical signals
RS-485 to RS-232
Translates protocols
DH-485 to DF1
Configured thru the backplane (Series B)
DH-485 / RS-232
ACT
BA LOW
485
CFG
DF1
FAULT
H/D
F/D
RS-232
Config
RS-232
DF1
RS-485
DH-485 24

30. 1747-KE Module RS-485/DH-485 to RS-232C/DF1 interface module
DH-485 / RS-232
ACT
BA LOW
485
CFG
DF1
FAULT
H/D
F/D
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 23

31. Typical KE Configurations
RSLogix 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
Modem
Modem
SLC 500
DH-485
Isolated Link
Coupler
1747-AIC
SLC 5/01 25

32. Typical KE Configurations
Master
Master/Slave communications
Polled Network
Using Channel 0 w/ DF1 Half-duplex Slave
DF1 Master (RSView)
Modem
Slave(s)
Modem
Modem
Modem
Modem
SLC 500
with KE
SLC 5/02
with KE
SLC 5/01
with KE
RSLogix 500 Programming
Software 26

33. 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
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
Setup Screen
Read/Write Message
Read/Write Read
Target Device CPU
Control Block ?
Control Block Length
MSG
( EN )
( DN )
( ER )
Local/Remote Local
Type Peer-To-Peer 28