High Volatge cable splicing and clearance requirements

[elecsun]

We plan to lay 3Runs of 15kV grade Cu/SC/XLPE/SC/Cut/PVC/SWA/PVC cable in umderground.Cable length is about 2500Mtr and Cable drum length is 500Mtr.So obviously it requires splicing.My question is whats the clearence required between the cables at splicing place and does that splicing should be inside concrete inspection pit?Is there any inetrnational standard specification available?Cable experts guidence please .......

 

[wareagle]

elecsun
Many times cables such as you have are installed in the same conduits so spacing need not be a great concern. I would say you need enough room to work on the splice if it needs to be replaced. You will need a man hole or splice box of some sort. The splices should be available to inspection. You will need enough room to make the pulls. You also need to make the pulling caculations to verify that the distance between the pulls is not too great.
Depending on the size of the cables and the number of bends
500 ft may be too long. You didn't say if this was underground.

 

[elecsun]

Dear wareagle
i mentioned that, cable is layed and buried underground 1.5 meter deep.What about splicing clearence required between 3 cables layed about 150mm apart?cable laying experts guidence please .....

 

[jghrist]

In the USA, there are no particular requirements for spacing between splices. Direct burial of splices is common. All three phases should be spliced close to the same point with the shields bonded together and connected to ground rods. See RUS standard drawing UM48-3 in Specifications and Drawings for Underground Electric Distribution available at

http://www.usda.gov/rus/electric/bulletins.htm

 

[cuky2000]

Since the splicing insulation should be equal or greater than the cable, insulation this should be sufficient even if the cable and splicing are touching next to each other. Therefore, clearance from the electrical point of vie should not be a concern

Statistics shows that splicing is a potential weak point in the cabling system, therefore provision should be considered for inspection and replacement in case of a failure or testing. A handhold or manhole may be a good alternative for easy inspection, testing and maintenance. If the cable is installed direct buried, the splicing should be spreading in the smaller practical area.