The use of graphic symbols and text symbols in circuit diagram implementation is an essential aspect of the PLC (Programmable Logic Controller) profession. These symbols act as a universal language that helps in communicating complex electrical and electronic concepts in a simplified form. In this article, we will discuss the importance and implementation standards of graphic and text symbols in circuit diagrams for PLC technicians.
First and foremost, let's understand the difference between graphic symbols and text symbols. Graphic symbols are visual representations of electrical and electronic components, while text symbols are alphanumeric characters used to label and identify components or connections in a circuit diagram. Both types of symbols are crucial in creating accurate and easily understandable circuit diagrams.
Now, let's look at the importance of using these symbols in circuit diagrams. As PLC technicians, our work involves designing and troubleshooting complex control systems. These systems often consist of multiple components and connections, which can be challenging to represent and comprehend in a written description. Here, graphic symbols come to our rescue by providing a concise and standardized way of representing components in a circuit diagram. Similarly, text symbols act as labels, making it easier to identify connections and understand the flow of the circuit.
The implementation standards for graphic and text symbols in circuit diagrams are established and maintained by the International Electrotechnical Commission (IEC). The IEC is responsible for developing and publishing international standards for electrical and electronic technologies, including symbols and notations used in circuit diagrams. These standards are essential as they ensure uniformity and clarity in circuit diagrams, regardless of the manufacturer or country of origin.
One of the most commonly used standards for graphic symbols is the IEC 60617, which defines graphical symbols for use in circuit diagrams. This standard categorizes symbols according to their function, such as input devices, output devices, and power supply components. Another widely used standard for text symbols is the IEC 81346, which specifies a uniform identification system for objects in technical installations. This standard includes guidelines for labeling components, identifying connections, and creating reference designations in circuit diagrams.
In addition to the IEC standards, there are also regional standards for graphic and text symbols, such as the American National Standards Institute (ANSI) and the National Electrical Manufacturers Association (NEMA) standards in the United States. These standards may have slight variations from the IEC standards, but they ultimately serve the same purpose of providing a standardized language for circuit diagrams.
As PLC professionals, it is essential to adhere to these implementation standards to ensure the accuracy and consistency of our work. It also helps in avoiding confusion and misinterpretation, especially when working on projects that involve collaboration with technicians from different countries or regions.
Now, let's talk about the common graphic and text symbols used in circuit diagrams. Some of the commonly used graphic symbols include a circle for a digital input, a square for a digital output, and a triangle for a control relay. These symbols are universal and can be easily recognized and understood by technicians worldwide. Similarly, text symbols such as "NO" for Normally Open and "NC" for Normally Closed are widely used to indicate the status of a device or connection in a circuit diagram.
It is worth mentioning that while these standards provide a set of commonly used symbols, they are not exhaustive. As PLC technicians, we may come across symbols that are not included in the standards. In such cases, it is essential to maintain consistency and clarity by using a symbol that closely represents the missing component or function.
In conclusion, graphic symbols and text symbols play a vital role in the creation and interpretation of circuit diagrams for PLC technicians. The implementation standards set by organizations like IEC and ANSI ensure uniformity and clarity in these symbols, making it easier for us to understand and communicate complex electrical and electronic concepts. Adhering to these standards is crucial for creating accurate and easily understandable circuit diagrams, ultimately leading to efficient and successful control system designs and troubleshooting.
Remember, as professionals, our work is not just limited to understanding and implementing these symbols, but also educating others about their significance and ensuring their proper use in all our projects. Let's strive to maintain the highest standards of professionalism in our work, starting with the use of graphic and text symbols in circuit diagrams.