Shower Cable

[DuaneMHunt1976]

With shower say 10mm is dam hard to move, would 2x6mm or 6mm+2x2.5mm as being more manageable
Still the same cross sectional area

 

[hasel5]

1mm has a ccc around 12/13A depending on conditions, let's say 10A for ease of maths.
So for a 40A supply you would only need 4off 1mm cables.

This is the way forward

 

[baldsparkies]

This is the way forward

Use a 2.5mm and limit the running time of the shower to 2 minutes 12 seconds using a timer.
Set the timer to re energise after 10 minutes to allow for thermal effects.

Check the calcs yourself if you don't believe me:jester:

 

[hasel5]

Use a 2.5mm and limit the running time of the shower to 2 minutes 41 seconds using a timer.
Set the timer to re energise after 10 minutes to allow for thermal effects.
Check the calcs yourself if you dont believe me. :conehead:

I believe you but don't let everyone know lol.
I am retiring to the pub for the rest of the day.

to contemplate my future

 

[uksparks]

I have just read this and my thoughts are, why are people even talking of using more than one cable, just use the "correct" size and do it properly, anything other than that is just stupid IMO.

 

[hasel5]

See post 10

 

[Andy78]

I have just read this and my thoughts are, why are people even talking of using more than one cable, just use the "correct" size and do it properly, anything other than that is just stupid IMO.

I don't think anyone is being serious petal. Maybe the OP, but even then I think this thread was possibly a joke that didn't translate to the internet very well.

 

[baldsparkies]

I don't think anyone is being serious petal. Maybe the OP, but even then I think this thread was possibly a joke that didn't translate to the internet very well.

Well lets face it you either laugh or cry when reading the OP's comments.
Lets hope he IS joking, scary stuff.

 

[davesparks]

OK how long you been in that pub Dave, I'm jealous. :wink_smile:

I haven't got near the pub yet, but it's exactly the same maths that would give you four cables with a ccc of 100A to carry a 400A supply or of 1000A to carry a 4000A supply.

The only difference being that nobody in their right mind would use paralell cables to carry a 40A supply!

 

[GMES]

Totally agree with Dave on this one,when you are installing large supplies sometimes you have to install large cables in parallel because the cables can become unmanageable however the same does not apply when installing a shower cable.

 

[telectrix]

Totally agree with Dave on this one,when you are installing large supplies sometimes you have to install large cables in parallel because the cables can become unmanageable however the same does not apply when installing a shower cable.

agreed.most showers will run happily on a 2.5mm, strung over the bath and second duty as a knicker dryer.

 

[Dave OCD]

All joking aside though, I think anything over 9.5kW on an instantaneous electric shower is getting a bit ridiculous and unnecessary too.

 

[baldsparkies]

All joking aside though, I think anything over 9.5kW on an instantaneous electric shower is getting a bit ridiculous and unnecessary too.

That's the fun Christmas day, when Mums cooking the Turkey, Dads watching his 65" plasma with the electric log affect fire on full blast, and the teenage daughters washing her hair in the 10.5kw shower.
Poor old 60A cut out fuse says stuff this and pop !! Merry Christmas.

 

[Dave OCD]

Precisely.:tongue3:

 

[baldsparkies]

Totally agree with Dave on this one,when you are installing large supplies sometimes you have to install large cables in parallel because the cables can become unmanageable however the same does not apply when installing a shower cable.

Count me in.
Tri-rated is another that can make those awkward break your fingers and scuff yer knuckles moments an easier option.
Have needed to fit parallel sub main runs myself on heavy installs and that's perfectly logical.
But cabling a domestic shower this way is nonsense in the extreme.
I think common sense and good electrical practice are the words of the moment with this one.

 

[Marvo]

I'd be interested to know if there's actually a reg that forbids it in the UK, I know there isn't in our domestic regs. As said already, it's common practice with cables in larger distribution networks but the logistics of ensuring identical lengths, routes and connecting a parallel cabled domestic final circuit would make it a bad idea.

 

[uksparks]

I think id be more concerned about one of them being disconnected then overloading the remain one.

 

[Richard Burns]

I'd be interested to know if there's actually a reg that forbids it in the UK, I know there isn't in our domestic regs. As said already, it's common practice with cables in larger distribution networks but the logistics of ensuring identical lengths, routes and connecting a parallel cabled domestic final circuit would make it a bad idea.

BS7671 specifically permits paralleling cables, with certain provisos on cable route, type, etc. to ensure equal current sharing.
However I believe it is directed mainly toward the larger cable sizes in reality.

 

[davesparks]

I think id be more concerned about one of them being disconnected then overloading the remain one.

That's kind of why there is specific guidance on the design and protection of parallel feeds in bs7671

 

[vjsmarwick]

You will not need to worry in another few years because of the EU the power of vacuum cleaners are being restricted next they are going to restrict our power tools so soon your showers will be a maximum of 3KW and you will have a fine mist spray to that you reduce your need for so much water and then to round it off your bath towels will be the size of face cloths ! pmsl

 

[Leesparkykent]

You will not need to worry in another few years because of the EU the power of vacuum cleaners are being restricted next they are going to restrict our power tools so soon your showers will be a maximum of 3KW and you will have a fine mist spray to that you reduce your need for so much water and then to round it off your bath towels will be the size of face cloths ! pmsl

It's already in action. Companies are prohibited from manufacturing or importing any vacuums with motors above 1,600 watts and will have a further reduction in 2017 to 900 watts. What a joke lol.

 

[R G]

Cant see why the op doesn't go for 2 x 8Kw showers side by side with a 6mm T&E for each, LOL....

 

[baldsparkies]

And not 1 person as mentioned the common practice of connecting 2 x 2.5mm cables 2 a 32A breaker !!
Sound familiar !!! :icon12:

Yea but! no but! yea but!

 

[stevethesparks]

Cant see why the op doesn't go for 2 x 8Kw showers side by side with a 6mm T&E for each, LOL....

As long as the two pull cords are tied together to ensure isolation of both at the same time.

 

[Slowhand]

How would you test it? As a radial or a ring final circuit?
I'm not sure the resistances in parallel are such a good idea either.
Might be a good idea to check the fire insurance.

 

[Richard Burns]

A parallel circuit would be tested as a radial (possibly once for each cable), a circuit without identical conductors on the same route would be tested as a ring but must be constructed in accordance with the regulations with are fairly limiting on available design options and is generally not recommended except for the exception class of a ring final socket circuit.