IPC-2221 Electrical conductor spacing,B4-表層導体,永久性聚合物涂覆(任何海拔),Note: For example, B1type board with 600V:600 V - 500 V = 100 V0.25 mm + (100V X 0.0025mm)= 0.50 mm,Note: For example, B1type board with 600V:600 V - 500 V = 100 V0.25 mm + (100V X 0.0025mm)= 0.50 mm,
