One Controller - Any Bus Connecting Programmable Automation

Controllers ,Measurements, Sensors, Networks and PLCs

Ian BellNational Instruments

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Agenda

• Industrial Communications Overview• Why Connect a PAC to Industrial Networks and

PLCs?• 3 Methods to Connect to Any PLC or Device

Basic Analogue and Digital I/O Industrial Network Communication OPC

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Industrial Communications Overview

Industrial communications connect industrial devices such as PLCs, sensors and actuators

Common Industrial Networks

•DeviceNet

•PROFIBUS

•Modbus TCP

•Modbus Serial

•CANopen

•FOUNDATION fieldbus

•Interbus

•CC-Link

•LonWorks

•HART

•PROFINET

•Ethernet/IP

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PAC Architecture• Ruggedness and reliability of PLC• Software capabilities of PC• Modular and diverse I/O

Softw

are

Cap

abili

ties

Ruggedness and Reliability

PLCPLCPCPC

PAC

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Why Connect PACs to Industrial Networks and PLCs?

High-speed analogue measurements High-resolution analogue measurements Advanced analysis (digital filtering, frequency analysis) Custom hardware performance with FPGA technology

• High-speed closed-loop control• FPGA-based processing and analysis

Custom Sensors/Measurements

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PLCsPACs

3 Methods to Connect to Any PLC

Industrial

Communications

Basic I/O

Analogue/Digital

OPC

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Basic I/OCheap, Easy, Fast and Effective

• Available on every platform• Analog and digital I/O options• PLC users can easily integrate analogue and

digital I/O into their code• Allows PACs to act as intelligent devices

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Basic I/O

• Advantages Fast, deterministic, little or no software overhead

• Considerations Doesn’t scale well Point-to-point wiring (parallel) Can’t communicate lots of data

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ExampleAutomated Filling of Aerosol Cans

• Existing PLC system was being used to automate the filling of aerosol cans

• PLC did not have the capability to do high-speed analogue for pressure measurements

• NI CompactRIO PAC was used for high-speed pressure measurements on 8 channels (2 k per channel)

• CompactRIO and PLC were integrated using digital I/O

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PLCsPACs

3 Methods to Connect to Any PLC

Industrial

Communications

Basic I/O

Analogue/Digital

OPC

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Methods for Industrial Communications

Ethernet/SerialPlug-In Interfaces

Gateways over Ethernet, Serial

Versatility

Performance/Determinism

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Plug-In Communication Boards

• CAN and CANopen• DeviceNet• FOUNDATION fieldbus• Serial (RS232, RS422, RS485)• Third-party PROFIBUS (Comsoft)• Support for PXI, PCI, PCMCIA, and

CompactRIO

Plug-In Interfaces

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Plug-In Communication Boards

• Advantages Direct, deterministic communication with the processor Timing and synchronisation with other I/O (DAQ) High-level API support for LabVIEW and other programming

languages• Considerations

Many smaller buses and protocols are not supported Many only available on PC and PXI (real-time supported)

Plug-In Interfaces

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Example : PROFIBUS

• PROFIBUS master/slave for PXI and PCI

• More than 2 million nodes• Popular in Europe and Asia• Recommended: Comsoft DF PROFI II

interfaces

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cRIO-PBMaster/Slave and cRIO-PBSlave

cRIO PB Master/Slave module Supports operation as DP Master or DP

Slave Ships with configuration tool configurator

II for DP Master configuration Ships with GSD file to configure any DP

Master system

cRIO PB Slave module Supports operation as DP Slave Ships with GSD file to configure any DP

Master system

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Ethernet-based Industrial Protocols

• Modbus TCP/IP• Ethernet/IP• EtherCAT• Profinet

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Why Ethernet: ProtocolsModbus TCP/IP

Traditional Industrial Protocols

PROFInetPROFIBUS

DeviceNet EtherNet/IP

Modbus

Ethernet Physical Layer

CanOPEN EtherCAT

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Modbus TCP/IP Overview• First industrial protocol on Ethernet (introduced 1999) Based on Modbus developed by Modicon in 1979 Widely adopted and open Ethernet standard • Advantages Uses standard Ethernet (hardware and TCP/IP transport layer) Open and relatively simple • Disadvantages Not a hard real-time protocol Does not deliver determinism

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Ethernet-based Industrial Protocols

• Modbus TCP/IP• Ethernet/IP• EtherCAT• Profinet

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EtherNet/IP Overview

• Dominant bus for Rockwell Automation Managed by Open Device Vendors Association (ODVA) Extends DeviceNET concepts to Ethernet

• Advantages Uses Ethernet transport layer (TCP and UDP)

• Disadvantages Can overload networks with UDP messages if not correctly

configured, recommend managed switches with IGMP snooping

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Ethernet/IP Terminology

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Communication from NI PAC to ControlLogix and ComapctLogix PLCs

Ethernet/IP

Uses explicit messagingAvailable for download from NI Labs

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Third-Party Gateways

• Wide variety of communication buses and protocols supported

• Ethernet or serial-based• Perfect for non-PXI, PCI, and PCMCIA systems

Ethernet

PROFIBUSDeviceNetEthernetIPControlNet

Gateways over Ethernet, Serial

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ExampleAdding Vision for Food Processing Optimisation

• Needed NI Compact Vision System to calculate the mass/volume of the food item coming through on the conveyor belt

• Ethernet/IP connectivity was a requirement

EthernetIPModbus TCP

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PLCsNI PACs

3 Methods to Connect LabVIEW to Any PLC

Industrial

Communications

Basic I/O

Analogue/Digital

OPC

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What Is OPC?• Universal language for

reading and writing data

• OPC Client: Read and write to OPC

• OPC Server: Translates between OPC and device-specific protocols

English

Windows PC

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OPCClient

Allen-BradleyOPC Server

SiemensOPC Server

MitsubishiOPC Server

PLCsDevice-Specific

OPC Server

Windows PC

Ethernet/IP

PROFINET

CCLink

OPC ClientOPC

Driver

OPC Client

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NI OPC Servers for Third-Party PLCs

• OPC support for more than 100 PLCs• Connects with LabVIEW DSC OPC client

Evaluation version included with DSC

• Servers included for:•Allen-Bradley•AutomationDirect•Cutler-Hammer•GE•Hilscher

•Modbus•Omron•Philips•Siemens•Toshiba

•WAGO•Yaskawa•Yokogawa•…and more!• ni.com/opc

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OPC• Advantages

Most universal Least device-dependent Ideal for HMI and SCADA applications

• Considerations Slower, not deterministic, single-point only Can require PC-based OPC servers Not for safety or critical communications

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ABCO Adds LabVIEW to PLC System

• ABS brake testing system• PXI for high-speed encoder

measurements• Added to existing Allen-Bradley PLC

assembly line• OPC used for communication

between PXI and Allen-Bradley PLCs

“The ease by which NI can speak to the Allen-Bradley hardware saved me valuable time on this delivery-critical job.” -Arif Bustani, electrical engineer ABCO

“The ease by which NI can speak to the Allen-Bradley hardware saved me valuable time on this delivery-critical job.” -Arif Bustani, electrical engineer ABCO

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Summary• PACs add flexibility to connect to anything• Use PACs to add any measurements to existing

system• 3 Methods to Connect PAC to Any PLC:

Basic Analogue and Digital I/O Native Industrial Communications OPC

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Online Resources ni.com/commni.com/pacni.com/labs

www.modbus.org – Modbus TCP/IPwww.odva.org – Ethernet/IPwww.ethercat.org – EtherCATwww.profibus.com/pn - PROFINET