Which NEMA symbol represents a magnetic overload relay?

The correct symbol for a magnetic overload relay is represented by Symbol A. In the context of NEMA (National Electrical Manufacturers Association) symbols, the magnetic overload relay is specifically designated to visually convey its function and purpose within electrical systems.

Understanding the function of a magnetic overload relay is essential: it's a protective device that prevents motors from overheating due to excessive current. When the current exceeds the set threshold, the relay trips, disconnecting the power supply and safeguarding the motor from potential damage. Therefore, recognizing this symbol is crucial for electricians and technicians who must interpret schematics and ensure proper installation and maintenance of electrical systems.

Although other symbols are associated with different components or devices within electrical systems, they do not represent the magnetic overload relay. Recognizing these differences in symbols helps in understanding the layout and functioning of electrical circuits, ensuring the correct identification and troubleshooting of components in the field.