The protection range outside the two needles shall be determined according to the calculation method of a single lightning rod, and the protection range between the two needles shall be calculated as follows:
The protection range on the outside of the two pins shall be determined by the calculation method of a single lightning rod, and the protection range between the two pins shall be calculated by pressing:
The protection range outside the two poles shall be determined according to the calculation method of a single lightning rod, and the protection range between the two poles shall be calculated according to the following formula: