3.4EarthingConnection

3.4Earthing Connection

3.6EarthingConductor

公路工程thing conductors that are laid across different floors or at the same floor with long lay

ors that are laid across different floors or at the same floor with long laying

3.7TheTypesofEquipotentialBonding

3.8TheAccessingWaysofVariousCables

3.13PowerDistributionSystem

3.14.1Indoor cabling racks and various metal parts must be earthed, and electrical c

5.1Duringselectionofroutingofopticalcable,followingsusceptiblezonesoflightningaccide ll bekeptfaraway: 1Where a sudden change occurs to the soil resistivity pio at the depth of 1Om. 2The junction of rockymountains and rice paddies or rivers, the boundary of mineral reserv boundaryofmountainforestsandgeologicalfaultzones

4.1GeneralRequirements

4.2TheTypesofEarthingandBonding

heTypesofInternalEquipotentialBonding

4.4 EarthGrid

Fig.4.4.2Connection of ring rmain earthing conductor and earth grid 3 Besides at four corners of buildings, the ring main earthing conductor and the ring ea ctrodeshallbeinterconnectedonceeveryotherpillar

5The Earthing of the Cables Entering into Burea

TheLightningProtection andEarthingofCable

5.1ExchangeBureau andDataBureau

5.2AccessNetworkStationandModuleBureau

5.3.1Equipmentofuserunits ofbroadbandaccess sitesmustbeearthed.

.2For the earthing of user units of broadband access sites, rebars in the building foundation shall ectlyusedas theearthelectrode

5.4FiberCableRepeater Station

TheLightningProtectionandEarthingof

6.1GeneralRequirements

6.2.5Theearth grid form shall be in aco

be designed according to Fig.6.2.7

Che Earthing of Antenna and Feeding Cable

6.4.2For feeding cables and coaxial cables, one earthing bar shall be set at the feeding cable window of equipment room, being used as the earth point of feeding cables.The earthing bar shall be connected with the earthgrid directly

医院建设标准6.7.2Main earthing conductorsandmain earthingbars(earthingreferencepoints)shall be setcloseto Histribution boxes and thefirstlevelpower protectors,whichshallberegarded as the referencepoint, and then connected with equipment earthing bars via multistrand copper wires with the sectional area largerthan 7OmmTheearthingof all equipment shall takethis potential asthe referencepoint for equipotential bonding. 6.7.3Whenoneearthingbar is used in aequipment room,thestarearthingmode shall beadopted, and corresponding screwholes shall be reserved;the first level SPD,distribution boxes,optical cable metal intensive cores and metal protective coverings, the ground of DC power, the ground of equipment, enclosures, cabling racks etc.shall be earthed at the place nearby,and earthing conductor shallbeshortand straight. 6.7.4When two earthingbars areused in a equipment room,thefirst earthing bar should be connected with the first level SPD,distribution boxes, optical cable metal intensive cores and metal protective coverings;the second earthing bars should be connected with the ground of equipment the ground of DC power enclosures,cabling racks.The first earthing bar shall be connected with the earth grid directly.All earthing conductorshallbeshortand straight

6.8.2Main earthing conductors in equipment rooms shall havereliable connection with earthing connections.Main earthing conductors should be laid in ring shape in equipment rooms along interior walls or geosynclines,cabling racks,and coppermaterials with the sectional area not less than9Omm? or16Omm’hot dip galvanized steel flats should be adopted.Several earthing bars may be set at the main earthingconductor.The earthingbar shallbethecopperplatewitha sizenotlessthan 4oOmmX 1oOmmX5mm,andcorresponding screwholes shallbereserved. 6.8.3All earthing bar and earthingconductors in equipment rooms shall be clearlymarkedwithlabels that cannot easilybedamped or fall off,indicating namesof earthing conductors and names of connected equipment at two ends of the earthing conductors;the earthing conductors should adopt green and yellow cables, and shall be fastened tight and neatly, and bending should beavoided.

TheLightningProtectionandEarthingof

7.1GeneralRequirements

7.3Direct LightningProtection

TheLightningProtectionandEarthingof

新闻出版标准TheLightningProtectionandEarthing of Mici