Programmable Logic Controllers and Communications Systems - Intro Treatment (2 Contact Hours)

Learning Objectives for California Water Treatment – PLCs and Communication Systems Module

Module 1: Digital Fundamentals and Binary Systems

• Understand the binary numbering system and how bits and bytes are structured and interpreted.

• Identify how digital logic is applied in PLC programming and instrumentation.

Module 2: Communication Protocols and ASCII Encoding

• Explain the function of ASCII and its role in digital communication systems.

• Describe serial communication protocols (RS-232, RS-422, RS-485) including wiring standards, transmission direction, and data rates.

Module 3: Ethernet and LAN Technologies

• Compare LAN configurations such as peer-to-peer, domain, and star networks using hubs and switches.

• Describe Ethernet standards, MAC addressing, collision detection (CSMA/CD), and Power over Ethernet (PoE).

Module 4: Fiber Optic Communication

• Understand the structure and benefits of fiber optic cable and distinguish between single-mode and multi-mode applications.

• List advantages and disadvantages of fiber optic systems in SCADA networks.

Module 5: IP Networking and Data Transmission Protocols

• Define key internet protocol layers (IP, TCP, UDP) and their roles in routing and delivery.

• Explain how networked PLC systems communicate using Modbus TCP and EtherNet/IP.

Module 6: PLC Basics and Ladder Logic

• Describe the history and purpose of PLCs in automation, including advantages over traditional relay systems.

• Identify the components of a PLC system: CPU, input/output sections, power supply, and communication interfaces.

• Interpret simple ladder logic diagrams and explain how they emulate relay logic.

Module 7: Analog and Digital Input/Output Systems

• Differentiate between digital and analog inputs and outputs and how signal conversion (A-to-D, D-to-A) works in a PLC.

• Identify the importance of bit resolution (e.g., 12-bit vs. 16-bit) for accuracy in analog signal processing.

Module 8: Remote I/O and Modular Design

• Explain how remote I/O modules extend PLC capabilities and identify best practices for modular expansion.

• Recognize hot-swappable components and troubleshooting techniques using status LEDs.

Module 9: SCADA Integration and HMI Systems

• Describe how PLCs connect to SCADA systems for data collection, trend logging, and real-time operator interaction through HMI touchscreens.

• Discuss the evolution and benefits of modern SCADA over legacy systems.

Module 10: Wireless Communication and Radio Systems

• Explain the use of radio telemetry in water system SCADA applications, including Multiple Address Systems (MAS) and spread spectrum radios.

• Identify factors affecting radio signal performance, including antenna type, frequency, line-of-sight, and power settings.