Ground Connection and Zero range of applications suitable protective earth neutral grounding grid. Three-phase four-wire neutral grounding grid should be used to protect access to zero measures. Since all dielectric breakdown or other reasons may present a hazardous voltage metal parts should be taken to ground or zero. 1, should be taken to ground or zero devices 1) motors, transformers, electrical appliances, lighting equipment, portable and mobile electric appliances such as metal, base and gear attached thereto. 2) metal structures or reinforced concrete as well as indoor and outdoor power distribution unit near energized parts of the metal cover fence, fence or a metal gate. 3) distribution panel, console, console, control box of the metal frame or enclosure. 4) transformer secondary winding. 5) AC-DC power cable boxes metal, metal sheath of steel pipe and cable wiring. 6) fitted with a metal rod lightning line power lines and reinforced concrete tower. 7) mounted on Distribution Feeders switches, capacitors and other electrical equipment. 1) Leung: some design considerations when ceiling height without taking into account the height of the beam. Due to the large span substation, sometimes up to beam height 800mm, so the mention of civil conditions should be considered storey height of the beam. 2) Duty: Some designs will duty room located in inaccessible in the corner. This is incompatible with the provisions of section 4.1.6 of the power distribution room GB50053-94, which states "manned substation Henan distribution room, duty room should be set separately. High voltage power distribution room and duty room should be straight or through Nanyang distribution channel communicating room construction, duty room should have direct access to the outdoors or walkway leading to the door. "3) Cable channel: Some double substation low voltage distribution panel disposed only at the bottom and rear side panel trench, between two rows of mutually connected screen ditch. For easy access and future adjustment of the cable lines, should all primary cable channel and control all communication with the internal cable channel. Henan high and low voltage power distribution room _ Teflon (certified) _ distribution room provided by Nanyang Fu Long Electric Power Engineering Company Limited. Nanyang Fu Long Electric Power Engineering Co., Ltd. (www.nyfulong.com) is Nanyang, Henan, transmission equipment and materials leaders, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. Teflon power in leadership with the staff warmly welcome all inquiries negotiations to create Teflon electricity better future.