PLC Development 2010gMichael Kellow

Kathleen ManuelJames Kemp

www.2010g.info

Overview

• Description• Scope• Current Progress

• Communication• Software• Hardware

• Future Plans2

PLC’s Control the World

3

PLC Industries

• Water & Waste Treatment• Electricity Generation and Distribution• Mining• Manufacturing• Pharmaceuticals• Golf Clubs

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What makes a PLC

Programmable Logic Controller

• Simple Logic Controller• Reliable• Extendable• Versatile

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PLC vs PC or Micro

• Less Errors in Programming• High Reliability• Compatibility with Hardware and

Instuments

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PLC Range

16 Major PLC Manufacturers

Many Smaller Manufacturers

Not Compatible with each other

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Scope

Research, develop and construct an industry standard PLC (programmable logic controller)

for teaching purposes.

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Current Progress

PLC Development

Communications Protocol Software Hardware

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Communications Protocol

Some of the factors that will help determine which type of protocol to use:

• cost• redundancy• speed• repeatability• maintainability

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Communications Protocol

Modbus • Developed by Modicon• Standard communications protocol in industry• Widespread use of Modbus in industry mainly due to:

– Cost – Maintainability

Image taken from: www.rtaautomation.com/modbustcp11

Communications Protocol

Ethernet/IP• Developed by Rockwell Automation (Allen-Bradley)• Designed for use in process control and other automation

applications

Image taken from: ethernetgateways.com12

Current Progress Software

• Kernel Design• SLC 500 Commands• Closed Source• PID Control• Ladder Logic Interpreter

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Ladder Logic

[ I2 AND NOT (O3) ] OR [ O3 AND NOT (I2) ] = Output 214

Programming

RS Logix 50015

Hardware

Enclosure

Processor Module

Communications Modules

Expansion and I/O Modules

Power Supply

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Future Goals

http://www.wastechcontrols.com/images/plc.jpg17

Questions