Right size swa

[skystorm]

eveng all,

Would appreciate your input on the following.

How do i go about picking the right size swa cable to use, on single phase using 32 amp braker or 3 phase

 

[Bez]

That all depends on the circuit design, what is it going to be used for?

Calculate demand

Choose correct size cable to carry demand current

choose correct size protective device

 

[NozSpark]

If you don't know you should be calling an electrician,,,

There are a lot of factors to take into account such as--

single / 3 phase

maximum demand

earthing type (TNS, TNCS or TT)

the earth loop impedance (Ze)

current carrying capacity

the protective device protecting the cable

installation method

volt drop

earth loop impeedance

When you know these you look up the appropriate tables in BS7671:2008 and do the necessary calculations.. then and only then will you be able to determine the size of cable that you need to use

I would suggest that you need to call an electrician..

 

[Andy™]

eveng all,Would appreciate your input on the following.

How do i go about picking the right size swa cable to use, on single phase using 32 amp braker or 3 phase

you need a lot more info than just MCB size. you need to know length, volt drop etc. bit more info and youll get better answers

 

[Riggy]

Ignore the "call an electrician" reply's - not in the spirit of this forum.

I notice in previous posts you have freely shared your knowledge in your area of expertise, so I'm sure those of us with sufficient confidence not to feel threatened by your question can return the favour.

As Andy says, give us as much info as you have and we'll make an informed guess (that's all it is after all!)

 

[skystorm]

call an electrician i like that .single phase 5 metres length, volt drop will be 5% 4m swa to feed an outside socket thanks

 

[NozSpark]

I'm sorry if my reply came across like that, on re-reading it I can see that I left a bit in that I meant to delete (first line), I don't like the "get an electrician" responses either...this forum is after all run to impart knowledge to all that ask,,

:coat :coat

saying that, cable sizing is something that shouldn't be guessed!

 

[skystorm]

Sorry about that Nozspark, I am an electrician working out in Afgan got a few hours off, Just went blank,

 

[NozSpark]

Have you got it figured out yet??

If not what's the demand & length of run??

 

[wozz]

what sort of work you doing in afgan skystorm?

 

[skystorm]

electrician' and satallites and aeriels Installer, CCTV

 

[wozz]

so are you in the forces then? sorry if it seems im being nosey.

 

[skystorm]

NO a civvie working out in the sand