What does the term "normal" gradient refer to in train brake systems?

The term "normal" gradient in train brake systems refers to the gradient that exists when the system is fully charged. In this context, a fully charged system indicates that the brake pressure is at the correct operational level for typical braking scenarios, allowing for effective control of the train. The normal gradient is important because it establishes the baseline conditions under which the braking system is expected to function properly.

Understanding this concept is crucial for operators, as it helps them gauge whether the train's braking system is functioning within expected parameters. If the gradient deviates from this normal state, it may indicate issues with the brake system's performance, prompting further inspection or adjustments.