How To Choose A Surge Protector For A Rooftop Distribution Box - Lightning Protection Experts Teach You How To Buy Quickly
How to select the surge protector for the rooftop distribution box? Article 3 of Section 5.4.3 of GB 50343-2012 stipulates: For AC power supply lines entering the building, at the junction of LPZ0A or LPZ0B and LPZ1 areas such as the main distribution box of the line, a surge protector of Class I test or a surge protection device of Class II test should be installed as the first level of protection;
National standard interpretation: You can choose either a first-level surge or a second-level surge protector.
Basis for selection of surge protective device
The national standard stipulates that the flow rate of the surge protector can be different for buildings with different protection levels. Therefore, how to select the surge protector specifically, first of all, it is necessary to determine the lightning protection level of the building.
National standard GB 50343-2012 Section 4.3.1: The electronic information system of the building can be classified according to Table 1-2 based on its importance, economy and value.
How to select a surge protector for a rooftop distribution box - distribution box
If your project is a first-level protection building, you can choose a first-level surge protector of more than 20KA. If you want to choose a second-level surge, you need to choose a surge protector with In≥80KA. From an economic point of view, the cost of a second-level surge with In exceeding 80KA is almost the same as that of a first-level surge. It is recommended that the rooftop equipment directly use a first-level surge protector, which has a larger flow rate and more durable lightning protection.
How to select a surge protector for a rooftop distribution box, and other building classifications are analogous to the requirements in the table. At present, the most common first-level surge protector is 25KA, which is almost the same cost as 15KA. The service life of a surge protector with a larger flow rate will be longer.
