Figure 5
On the left, the lowest step displays a green train icon positioned above a horizontal ledge, labeled “Minimum P M threshold value”. In the center, a slightly higher step shows a yellow train icon above a ledge labeled “Optimum P M threshold value”. On the right, the highest step displays a red train icon above a ledge labeled “Maximum P M threshold value”. The three steps rise progressively from left to right.Critical threshold levels for PM tasks of HVC in rolling stock