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 3
SLC 500 Communications
Network Topologies
Daisy-Chain
– Each device has two sections of cable tied together
– Each end has termination (resistor/capacitor)
Examples
DH+
DH-485
Remote I/O
SLC
SLC
Beldon #9463 cable
SLC
SLC
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SLC 500 Communications
Network Topologies
Star
– All devices physically connected at one point
Example
Ethernet
PLC
PLC
PLC
PLC
5
SLC 500 Communications
Network Topologies
Trunk-Line / Drop-Line
– 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
Trunk Line
Drop Line
SLC
Drop Line
SLC
Drop Line
SLC
Drop Line
SLC
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SLC 500 Communications
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
#1
#3
#2
SLC
SLC
#4
SLC
SLC
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SLC 500 Communications
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 ?
#1
Reply !
SLC
(Slave)
#2
SLC
(Slave)
#3
SLC
(Slave)
#4
SLC
(Slave)
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SLC 500 Communications
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
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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
What the hell do
all these mean?
RS-485
DH-485
REMOTE I/O
DF1
DH+
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SLC 500 Communications
A-B Communication Network Terms
RS-232
RS-422
RS-485
DH-485
}
Electrical Connections
}
REMOTE I/O
DF1
DH+
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
COMMS
FRENCH
ENGLISH
COMMS
ENGLISH
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SLC 500 Communications
Networks: DH-485 and DH+

Network Communications
– Program support and monitering
– Supervisory control for distributed hierarchy
– Operator interface for monitoring and control
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SLC 500 Communications
DH-485 Characteristics
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DH-485 Multi-drop link
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Daisy chain configuration
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Token passing system
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9.6 or 19.2 Kbaud data rate
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Connect up to 32 devices on network
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Up to 4000 cable feet (1200 meters) of network lenght
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SLC 500 Communications
DH485 Peer-to-peer Comms.
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Send/Recv messages from other SLC 500s
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Multi-master token-passing ring; 32 nodes

5/02, 5/03 + 5/04 can initiate communications to
other processors
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5/03 can using Channel 0, Channel 1, or both
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5/04 can using Channel 0 only
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Fixed and 5/01 respond only
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Initiate comms. with MESSAGE instruction in
ladder logic

NO ladder programming necessary to respond
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to a message from another processor
SLC 500 Communications
Typical DH-485 Network
ALLEN-BRADLEY
RUN
DTAM Plus
ALARM
PIC
AIC+
SLC 5/04
Link Coupler
Link Coupler
Link Coupler
SLC 5/03
SLC 5/02
SLC 5/01
Link Coupler
SLC 500 Fixed
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SLC 500 Communications
DH+ Characteristics
•
Peer-to-Peer Communication
– Utilizes Tolken Passing
•
•
•
•
•
•
64 nodes maximum
Remote Programming of SLC 500’S, PLC-2, PLC3, 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
RSLogix 500 Software
AI 500 Software
6200/AI Software
DH+
57.6Kbaud: 10,000 feet
115.2Kbaud: 5,000 feet
230.4Kbaud: 2,500 feet
Other
Processors
SLC-5/04
PLC-5
PLC-2, PLC-3
PLC-5/250
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SLC 500 Communications
DH+ to DH-485 Interface

Interface through a 1785-KA5
– Translate DH-485 <-> DH+
– Allows PLC5s and SLCs to communicate
SLC 5/04
RSLogix 500
Software
PLC-5
PLC-5
DH+
DH+
DH-485 Network #2
DH-485 Network #1
Link Coupler
Link Coupler
Link Coupler
Link Coupler
SLC 5/01
SLC 5/02
SLC 5/03
SLC 5/03
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SLC 500 Communications
RS-232 Communications
SLC-5/03 and 5/04 Support:

Full-Duplex (Point-to-Point)

Half- Duplex
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ASCII
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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
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Mulit-Drop, Single Master, Multiple Slave
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Slaves are Polled for Response from the Master
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Supports up to 255 Slave Devices
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Slaves: Any SLC Processor
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Master: PLC-5, SLC-5/03, 5/04, CV
SLC 500 Communications
5/03 + 5/04 Serial Port
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Point-to-point communications
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RS-232

Using Channel 0 w/ DF1 Full-Duplex
RSLogix 500
Programming Software
Modem
Modem
SLC 5/03 or 5/04
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SLC 500 Communications
5/03 + 5/04 Serial Port

Master/Slave communications
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Polled Network
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Using Channel 0 w/ DF1 Halfduplex Master or Slave
Master
DF1 Master (RSView)
Modem
Slave(s)
Modem
RSLogix 500 Programming Software
Modem
Modem
SLC 5/03
SLC 5/04
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SLC 500 Communications
ASCII Communications

5/03 and 5/04
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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
RS232
RUN REM PROG
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SLC 500 Communications
1747-KE Module

DH-485 / RS-232
ACT
485
CFG
DF1
FAULT
BA LOW
H/D
F/D
Converts electrical signals
– RS-485 to RS-232

Translates protocols
– DH-485 to DF1
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Configured thru the backplane
(Series B)
RS-232
Config
RS-232
DF1
RS-485
DH-485
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SLC 500 Communications
1747-KE Module
DH-485 / RS-232
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RS-485/DH-485 to RS-232C/DF1
interface module
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Acts as a BRIDGE between two
different networks or types of
communication
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Called a Bridge module
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(1) DH-485 port
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(2) Serial ports (RS-232, 422, 485)
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Allows remote communications to
SLC 500 systems
ACT
485
CFG
DF1
FAULT
BA LOW
H/D
F/D
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SLC 500 Communications
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.
Modem
Modem
SLC 500
SLC 500 CPU with KE module
• RSLogix 500 acts as if it were
directly on the DH-485
network
DH-485
Isolated Link
Coupler
1747-AIC
SLC 5/01
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SLC 500 Communications
Typical KE Configurations
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Master/Slave communications
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Polled Network
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Master
DF1 Master (RSView)
Using Channel 0 w/ DF1 Halfduplex Slave
Modem
Slave(s)
Modem
RSLogix 500 Programming
Software
Modem
SLC 500
with KE
Modem
Modem
SLC 5/02
with KE
SLC 5/01
with KE
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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 )
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