以 PL COMET CS400P 同軸保護器 coaxial protector male / female 手冊有載明 -- For a correct connection terminal grounding, use copper wire of 2.5 to 3mm in diameter ( 同軸保護器的接地需用2.5~3mm 直徑的銅線來拉到接地點). The end of copper wire grounding, should be buried to a minimum depth of 1 meter. (埋到地最少一公尺深) Or connection to ground and effectively verified.