How to Read Electrical Diagrams | Wiring Diagrams Explained | Control Panel Wiring Diagram

Summary

This video provides a comprehensive guide to understanding and reading electrical wiring diagrams, focusing on industrial control panels. It covers key concepts such as the importance of symbols, wire tags, and the general layout of diagrams. The video explains how to trace power flow, identify components, and navigate between multiple pages using grid references. It also introduces safety relays, interlocks, and the importance of understanding manufacturer-specific nomenclature. This tutorial is perfect for beginners and professionals looking to enhance their knowledge of electrical diagrams, with future videos diving deeper into PLC and VFD wiring.

Takeaways

• 😀 Understanding electrical wiring diagrams can initially be challenging, but with the right guidance, it becomes manageable.
• 😀 Electrical wiring diagrams can vary widely, from simple schematics for household appliances to complex 200-page diagrams for industrial control panels.
• 😀 Symbols used in wiring diagrams may vary depending on the software used (e.g., EPLAN vs AutoCAD Electrical), but they generally follow standardized conventions.
• 😀 The first step in reading a wiring diagram is becoming familiar with the symbols of the equipment used in the diagram.
• 😀 Wiring diagrams are typically read from left to right and top to bottom, but some exceptions may exist for better layout and clarity.
• 😀 Terminal blocks, circuit breakers, transformers, and safety components like relays and interlocks play crucial roles in industrial wiring diagrams.
• 😀 Wire tags on diagrams help with troubleshooting, enabling easy identification of where a wire should be connected in case of disconnections.
• 😀 Columns and page numbers in wiring diagrams are essential for referencing devices across multiple pages, improving navigation and clarity.
• 😀 Each electrical component in the diagram is referenced by unique tags, which help track and identify them in the physical wiring setup.
• 😀 A thorough understanding of a wiring diagram requires cross-referencing multiple pages to fully comprehend interlocks, relays, and power distributions.
• 😀 To understand complex systems like PLCs and VFDs, further parts of the series will focus on their wiring and signaling, ensuring a comprehensive learning experience.

Q & A

What is the first step in learning to read an electrical wiring diagram?

The first step is becoming familiar with the symbols used for the components in the wiring diagram. Each diagram should include a legend or abbreviation page that shows the symbols for various components like motors, solenoid valves, contactors, and fuses.

How should you typically read a wiring diagram?

You should read a wiring diagram from left to right and top to bottom, just like reading a book. However, some designers may make exceptions for better layout, as seen in the example where the diagram starts from the bottom.

Why are wire tags important in a wiring diagram?

Wire tags are essential for troubleshooting. They help identify where a wire should be connected if it gets detached from its connection point. Additionally, these tags are used to identify devices in the panel.

What does a 'Legend and abbreviation page' include in a wiring diagram?

The Legend and abbreviation page provides the symbols for various electrical components in the diagram, such as motors, solenoids, contactors, fuses, and relays. This page is key for understanding the diagram's layout and functionality.

How are wiring diagrams in different countries or industries standardized?

Wiring diagrams may follow different standards depending on the country or industry. They can vary in terms of voltage levels, frequency, layout, and the ECAD software used (e.g., EPLAN or AutoCAD Electrical).

What is the significance of 'X0' terminal strips in the wiring diagram?

'X0' terminal strips refer to a group of terminal blocks that have the same voltage level or serve the same purpose. They are used to organize the wiring and make the diagram easier to follow.

What is the meaning of 'NO' and 'NC' contacts in a wiring diagram?

'NO' stands for Normally Open contacts, and 'NC' stands for Normally Closed contacts. In a wiring diagram, these contacts are shown in their default state: NO contacts are open, and NC contacts are closed. This helps in understanding the normal operation of the circuit.

How are different devices located across pages in a wiring diagram?

Devices in a wiring diagram are identified using page and column numbers. For example, if a device on one page has the address '2.0', it means it's located on page 2, column 0. This system allows for easy cross-referencing between pages.

What role do safety relays play in an industrial wiring diagram?

Safety relays are used to protect people, material, and equipment during machine operation. They ensure that certain conditions, like safety barriers or an evacuated area, trigger the necessary safety functions in the system, such as closing NO contacts to enable power transfer.

What is the purpose of a transformer in an industrial wiring diagram?

A transformer is used to convert voltage from a higher level (e.g., 400 volts) to a lower level (e.g., 230 volts) to power specific equipment like receptacles, heaters, or fans. This ensures the correct voltage is delivered to different devices in the system.