2　Substation Site Selection and Layout

2.0.1　Site selection of substations shall comply with the current national standard GB 50187"Code for Design of General Plan of Industrial Enterprises"while satisfying the following requirements:

1　Substation shall be located closely to load centers.

2　Substation layout should minimize the land use through overall consideration of planning，construction，and operation requirements.

3　Site location shall be coordinated with the planning of urban and rural area or industrial and mining enterprises，and facilitate the routing of overhead lines and cables.

4　The site shall have convenient transportation conditions.

5　There should be no significant contaminations in the ambient environment.In the case of air pollution，the substation should be located in a manner to minimize the exposure to pollution sources.

6　Substations shall be located to avoid mutual influence with adjacent facilities.They shall be far away from facilities with potentiality of fire hazards or explosion as well as other sensitive facilities.Substations located adjacent to explosive gas atmospheres shall be designed according to applicable provisions of current national standard GB 50058"Electrical Installations Design Code for Explosive Atmospheres and Fire Hazard."

7　The site shall have favorable geological and topographic conditions，and should avoid important cultural relics or mineral reserves the mining of which may bring disturbance to the substation.If unavoidable，approval from relevant authorities shall be acquired.

8　The elevation of the site should be higher than the water level with an reoccurrence period of 50 years.If this requirement cannot be met，there shall be reliable flood protections，or local（industrial enterprise）flood protection criteria shall be met.However，the elevation shall at least be higher than the water logging level.

9　The main buildings of substations shall be in harmony with the surrounding environment.

2.0.2　The switchgear of substations shall be properly selected based on the regional characteristics.The seismic design shall comply with the current national standard GB 50260"Code for Design of Seismic of Electrical Installations".

2.0.3　In substations located at the center of cities，small-sized compact electrical equipment should be used.

2.0.4　The main transformer of substations shall be arranged at places with good transportation conditions and minimum noise disturbance to the ambient environment during operation.

2.0.5　The height of bounding wall of outdoor substations shall not be lower than 2.2m.The wall of substations in urban areas or enterprise substations shall be in harmony with the surrounding environment.

2.0.6　The main roads for fire protection in substations shall be 4.0m wide.The width of roads for transportation of major equipment may be determined based on transportation requirements，and shall allow vehicles to return.

2.0.7　The slope of the substation site shall be determined based on the equipment arrangement，soil quality，and drainage mode.It should fall in the range of 0.5%-2% and shall not be less than 0.3%.The slope in the direction of busbar shall meet the arrangement requirements of electrical equipment and structures.The maximum slope of roads should be no more than 6%.Where water is drained through roadside open trenches，the longitudinal slope of the trench should be no less than 0.5%.If difficult to achieve at particular positions，it shall be no less than 0.3%.

Cable trenches and other similar trenches should have a longitudinal slope of no less than 0.5% at the bottom.

2.0.8　The elevation of buildings and the embedded depth of foundation，road bed and pipelines inside a substation shall be well coordinated.The ground elevation of buildings should be 0.3m higher than that outside the buildings，and the walls of outdoor cable trenches should be 0.1m higher than the ground.

2.0.9　The minimum clearance between various underground pipelines，and that between underground pipelines and buildings，structures and roads shall meet the safety，maintenance，installation，and process requirements.

2.0.10　The greening of substation area shall be compatible with the ambient environment，and shall prevent plantings from disturbing the safe operation of electrical facilities.