SCADA System Fundamentals and Signals

A computer-based control system that monitors and controls industrial processes in the physical world.

A digital signal providing an ON or OFF input to a SCADA system.

A digital signal that provides a response from the SCADA system.

A continuous signal reflecting changes in monitored parameters like temperature or pressure.

A continuous signal representing the SCADA system's output command.

A local interface for accessing a SCADA system, often in remote locations.

A system for operators to interact with the SCADA system.

DI (Discrete Input), DO (Discrete Output), AI (Analog Input), and AO (Analog Output) are fundamental signals that a SCADA System uses.

A supervisory control and data acquisition system that is event-driven and operator-centric, focusing on data gathering and remote control.

A distributed control system that is process-state driven, locally controlled, and automatically responds to maintain predefined parameters.

A system that primarily responds to changes in state (events) rather than continuous monitoring.

A system that continuously monitors and regulates the state of a process to maintain set parameters.

A significant variation in the condition or status of a system or process that triggers responses in a SCADA system.

A method for a particular Programmable Logic Controller to communicate with other devices, often scanning for changes.

A system design where the operator, or human monitoring, plays a crucial role in taking action.

Measurable aspects of a process being monitored/controlled within a DCS.

A field device that interfaces with SCADA systems to control process outputs, typically for motors powering pumps and fans.

A versatile controller used to automate various tasks from nuclear plants to small systems, often including multiple IO modules, communication modules, and redundant configurations.

An advanced PLC with a computer processor, enabling better Ethernet network integration.

PLC programming can use various methods, including Relay Ladder Logic, Function Block Diagram, Structure Text, Instruction List, and Sequential Function Chart. Some PLC's may also have support for C++ or Basic.

An early PLC programming language, mimicking electrical wiring diagrams.

An international standard specifying five different types of programming languages used in PLC's.

Analog signals for speed indication and control, and discrete signals for status like running, fault, or start command.

May only include discrete signals and function as intelligent relays, usually are not expandable to add more inputs/outputs and have simple programming.

Licensed radio frequency band, typically 132-174 MHz and 400 MHz frequencies.

Licensed radio frequency band, typically 380-512 MHz, suitable for data transmission.

Unlicensed radio frequency, typically 900 MHz.

A two-radio system that transmits signals, specifically discrete or analog data from field devices to PLC's.

Directional antenna used for focused signal transmission.

Antenna that sends signals in all directions (360 degrees).

Frequencies like 2.4 GHz and 5.8 GHz, allowing for transmission of large amounts of data like video signals.

Transmission power is affected by the cable connecting the radio to the antenna.

Methods used to send data between SCADA system components.

Using Ethernet for communication in SCADA systems, reducing the need for special cables.

Two radios working together, only communicating with each other, eliminating wired connections.

Specific methods for exchanging data (e.g., MODBUS, Ethernet, ControlNET).

Using satellites for communication in remote areas, where radio or cable is unavailable.

A type of serial communication protocol specifically used in industrial settings.

Using cellular networks (e.g., PCS, CDPD) for SCADA communication.

Choosing the best communication method for a specific SCADA system based on needs.

Software allowing operators to interact with a SCADA system, focusing on graphics and control

Graphically displaying data over time to analyze patterns and improvements in a process

Recording and storing data from a SCADA system for future analysis and reference.

System alerts and notifications of important events or exceeding limits in a SCADA system.

Methods for improving efficiency and productivity by analyzing data in a SCADA system

Physical components (like computers and UPS or Uninterruptible Power Supplies) in a SCADA system.

Hardware (like radio or modem) that allows data transfer in a SCADA system.

Significant changes in pump activity detected by a SCADA system