Table 3 Defect classification of tree barrier [29]
From: Fast image recognition of transmission tower based on big data
Voltage level | Emergency defects | Major defects | General defects | |||
|---|---|---|---|---|---|---|
vertical distance (m) | horizontal distance (m) | vertical distance (m) | horizontal distance (m) | vertical distance (m) | horizontal distance (m) | |
110 kV | d v  ≤ 4 | d h  ≤ 3.5 | 4 < d v  ≤ 7 | 3.5 < d h  ≤ 6.5 | 7 < d v  ≤ 13 | 6.5 < d h  ≤ 12.5 |
220 kV | d v  ≤ 4.5 | d h  ≤ 4 | 4.5 < d v  ≤ 7.5 | 4 < d h  ≤ 7 | 7.5 < d v  ≤ 13.5 | 7 < d h  ≤ 13 |
500 kV | d v  ≤ 7 | d h  ≤ 7 | 7 < d v  ≤ 10 | 7 < d h  ≤ 10 | 10 < d v  ≤ 16 | 10 < d h  ≤ 16 |