10.8kW shower cable size

[trev]

10.8kw @ 230v=46.9A
10.8kw @ 240v=45A mate.

 

[Guest111]

10.8kw @ 230v=46.9A
10.8kw @ 240v=45A mate.

Come on Trev read the post properly he said 10800 Kw not 10.8 Kw

 

[trev]

Phil I swear I just saw your bit about a fundamental error and I said "10800kw for starter"
No idea where the post has gone
Update
That ones in the arms Dammit

 

[needasparks]

Example of reg 433.3.1 (ii).. would be fitting a 2way board with 2 x 16a mcb's you could effectively feed board of an Henley block in 6mm tails regardless of how large the fuse up-stream was because it cant draw long term a load exceeding the value of both mcb's.

This is like what was know as the busbar rule, with the reverse fusing. As far as i know its still acceptable as long as the fault protection covers upstream supply. But its one of the old school methods and would not be concidered by most now.

 

[beaver74]

table 4d2 is still for T+e bs6004 and gives a value of 52A in trunking or am I missing something

 

[Darkwood]

This is like what was know as the busbar rule, with the reverse fusing. As far as i know its still acceptable as long as the fault protection covers upstream supply. But its one of the old school methods and would not be concidered by most now.

Still see it alot, have you tried getting 25mm tails into a 2way board lol, but yes im currently fitting isolators of a 200amp busbar with tails from 16mm to 70mm coming off it into switchfuses.. waste of copper and money otherwise.

 

[cbw]

Well.....Bottoms to you all, I have a 10.8Kw shower at home and I installed it on the 40A 10mm circuit..............................

Its fine!

No melted cables, no house fire.

HOWEVER>>>> Would I do this at a clients house Hmmmmm?

Can you imagine trying to install 16mm T+E into an MK shower isolator?????

 

[DSpark1]

I agree with what was stated on the IET Forum to you, which is that Clipped Direct (C) is by far and away the most common reference method in a domestic installation. Also, as said, the shower is a fixed load which cannot overload and so the protective device need only provide fault protection.

but that would mean there no insulation in the property, and most if not all new builds have insulation in them so i can't see how it would b ref method c

 

[drew35]

I was surprised to see the other day a shower isolator light switch! I couldn't find a shower isolator so a search in the loft above revealed a 16mm cable to a sub board, with a double pole contactor as the isolator, switched by a light switch on the outside of the bathroom. This was a recently installed 10.8kw shower carried out by a bathroom company. So there's your answer, 16mm cable, contactor, rewire, rebuild etc!

 

[Knobhead]

DS, if you’re that worried about it put a 16mm in. Two forums have advised you, but you seem unwilling / incapable of taking advise.
Do it your own way!

 

[Des 56]

if you’re that worried about it put a 16mm in.





Or get one of these

​

Triton T80Z 7 5 KW Electric Shower White Chrome SP8007Z

 

[DSpark1]

10mm on a 50Amp breaker it is.

just wanted to be comfortable in understanding it so i can explain myself if I have to.

Thank you very much all

 

[beaver74]

table 4d2 is still for T+e bs6004 and gives a value of 52A in trunking or am I missing something

am I right or not ????????

 

[Risteard]

but that would mean there no insulation in the property, and most if not all new builds have insulation in them so i can't see how it would b ref method c

Rather than derating it's generally better to avoid the insulation! No reason why in almost all cases you shouldn't be able to prevent it being a factor.

 

[Darkwood]

If you have 400mm of 2/2 trunking fitted vertically where it passes through the insulation you really dont need to apply methods related to cable in trunking.... the trunking is open top and several orders larger than the cable so any thermal dissipation restrictions will be neglegible and clipped direct can be used as normal.

 

[DSpark1]

Thanks, yep point taken on the ref method.

 

[DSpark1]

table 4d2 is still for T+e bs6004 and gives a value of 52A in trunking or am I missing something

Table 4D5 on the 17th (green one) pg 340 is T+E

 

[beaver74]

Table 4D5 on the 17th (green one) pg 340 is T+E

yes I know that but it does not give ref method B(T+e in trunking)table 4d2 is also T+e but with other ref methods.
Am I not correct