What are the two types of emergency ratings in transmission systems?

The two types of emergency ratings in transmission systems refer to how the system can operate during unusual conditions. The correct classification is typically Long Term and Short Term.

When a transmission line or system experiences a fault or emergency situation, it must have a defined way to handle that stress. Long Term ratings apply to situations that may last for several hours. In contrast, Short Term ratings are reserved for more critical conditions that can occur over a shorter duration, often just a few minutes. These ratings are crucial for ensuring the reliability and stability of the electrical grid, allowing operators to manage unexpected situations effectively.

Normal and Emergency, while they seem intuitive, do not specifically categorize the duration of emergency conditions as Long Term and Short Term do. High and Low labels are not standard terminologies in the context of emergency ratings. Similarly, Transient and Steady State typically relate more to the types of electrical conditions rather than directly to how emergency situations are rated in duration.