cable size

[sparkyb2]

hello, can anyone help me , got to run a cable from a 11kv transformer to a 400amp main distribution unit which is 125m away, how do i calculate what size cable is required and is there a site where i can put in all the details in and it calculates this for me, thank you

 

[telectrix]

AEI Cables -- cable finder.

 

[Guest123]

I assume its an 11KV/400V Tx and you're installing the secondary???

 

[stef]

You have got the design current, you need toknow the protective device, calculate the tabulated current carrying capacity, then the voltage drop, then Zs = Ze + R1+ R2, then calculate the CPC . This is a verybrief description, all details are in the BGB. I assume you use SWA?

 

[Knobhead]

What size is the transformer? Is this the only load on the Tx or is there a distribution pillar acting as the feed.

 

[stef]

Over the thumb, I ' guess ' 240mm ...

 

[sedgy34]

hello, can anyone help me , got to run a cable from a 11kv transformer to a 400amp main distribution unit which is 125m away, how do i calculate what size cable is required and is there a site where i can put in all the details in and it calculates this for me, thank you

the cable suppliers will calculate this for you in there software cause they want the sale

 

[stef]

the cable suppliers will calculate this for you in there software cause they want the sale

Good tip. Yes they do.

 

[johnboy6083]

There's a lot more to this kind of install than meets the eye. Where is the neutral to be bonded? Do you know the nature of the load? Are you going to be using single core cables to feed the main DB?What primary over current device is to be used?

 

[Knobhead]

With out some details of the primary and secondry protection no one can tell you anything.