Programmable Logic Controllers and Applications for Marine Engineers and ETOs

Programmable logic controllers (PLCs) are used in a variety of applications in the marine industry, including propulsion systems, safety systems, data acquisition and motor starters. Marine engineers and ETOs must have a good understanding of these systems in order to maintain them in a safe and operational condition and to conduct efficient troubleshooting.

This book aids understanding of onboard applications and development of a systematic approach in the many troubleshooting cases likely to be encountered.

This publication is appropriate for:

• Management level marine engineers, operational level marine engineers, ETOs and electricians
• engineering cadets
• electrical engineering cadets
• anyone who is starting to work with PLC-based applications.

IMarEST members, please enter the promotional code ‘IMAREST’ during checkout for your members discount.

1. PLC Basics

1.1 Introduction

1.2 Power Supply Modules

1.3 The Input and Output (I/O) Interface

1.4 PLC-based Application Terminology

2. Inputs

2.1 Sinking and Sourcing Input

2.2 Discrete Inputs (DI)

2.3 Input Designations

2.4 Discrete Inputs Interface Devices

2.5 Wiring Discrete Inputs

2.6 Analogue Inputs

2.7 Inputs Expansion Modules

3. Process Monitoring Analogue Sensors

3.1 Pressure Transducers

3.2 Resistance Temperature Detectors

3.3 NTC Thermistors

3.4 Thermocouples (TC)

3.5 Proximity Sensors

3.6 Feedback Potentiometers

3.7 AC Current Measuring Transducer

3.8 Analogue-to-Discrete Converters

3.9 Safety Stop Relays

3.10 Analogue-to-Analogue Signal Converters

4. Outputs

4.1 Definition

4.2 Protecting PLC Output Transistors

4.3 PLC Discrete I/O Status Display

4.4 Analogue Outputs

5. Flowcharts

5.1 Definition

6. Numbering Systems and Conversions

6.1 The Decimal System

6.2 The Binary System

6.3 The Octal System

6.4 The Hexadecimal (Hex) Numbering System

6.5 The Binary Coded Decimal

7. Ladder Logic

7.1 Definition

7.2 Relay Function

7.3 Impulse Relay Function

7.4 Latching Relay Function

8. Function Blocks

8.1 Definition

8.2 Logic Gates

9. PLC-based Direct-on-Line Motor Starter

9.1 Counter and Timer Instructions

10. PLC-based Star-Delta Motor Starter

10.1 Star-delta Motor Starter Ladder Logic and Function Blocks

10.2 Star-delta Reversing Motor Starter LAD and FBD Program

11. PLC Communication and Networking

12. Troubleshooting PLC-based Applications

12.1 Troubleshooting PLC-based Applications

12.2 PLC Application Troubleshooting

12.3 PLC-based Application Troubleshooting Tips