1. There are three groups of grounding piles, namely forming grounding piles, HF welder grounding piles, and sizing grounding piles. Both the forming and sizing ground piles are located at one end close to the HF welder ground pile.
2. Grounding pile requirements (each group consists of 3pcs of steel tubes with φ48mm and length 3m, and the space between each steel tube is 2.5m to form an equilateral triangle, and the upper end is firmly welded together with 50 * 4 flat iron), the grounding resistance less than the specified value (0.4 Ω). Weld ground bolts to the nearest grounding point on each group of ground pile.
3. Three groups of ground piles are connected together with 50*4 flat iron.
