9.5 kw shower on 6mm ?

[jonthesparks]

just been to a job , saw that the shower 9.5 kw is on 6mm t&e the cable goes in the wall and under floor boards ,No insulation, to the board (A cable run of no more than 10 m) . I said downgrade the shower to 8.5 max. Is it really necessary ? never quite sure , its borderline to me .

 

[Guest123]

What is the rating of the MCB protecting the circuit??

 

[jonthesparks]

its
40 Amp

 

[jdd]

I don't think so, ref method C can take 46 amp.

 

[Guest55]

Not necessary to change shower , just make sure mcb is no more than 40A.
If it trips , it trips , no harm done

 

[Richard Burns]

Should just about be OK so long as there is no insulation about but really CCC is about 38A and you are running 41A, clamp the circuit and see what it is pulling. Doesn't comply at the moment but no need to change if it is working without damage, they are only on for a short time (tin hat).

 

[jdd]

Obviously breaker size should be 45A.

 

[Guest55]

Agree with richard , showers rarely used longer than 5-10 mins , too short a time for cable to heat up.

 

[robd]

Should be fine with a 40a in real life, be suprised if it trips, cable size just ok I'd say.

 

[Edd]

(A cable run of no more than 10 m) .

sounds a short run, why not price to upgrade to 10mm.. nice job, earn some money.

 

[sedgy34]

just been to a job , saw that the shower 9.5 kw is on 6mm t&e the cable goes in the wall and under floor boards ,No insulation, to the board (A cable run of no more than 10 m) . I said downgrade the shower to 8.5 max. Is it really necessary ? never quite sure , its borderline to me .

same here border line for me too i cant be arsed calculating it as others would slate it too

 

[sedgy34]

Not necessary to change shower , just make sure mcb is no more than 40A.
If it trips , it trips , no harm done

only customer got no shower

 

[Guest55]

Until he resets the mcb.
strewth.

 

[Farmelectrics]

I'd recommend upgrade to 10mm am I right in saying the breaker will take up to one and half times it's load which would pose a problem with the 6mm

 

[robd]

But 6 mm T&E can according to bgb can take 39a (I think without looking) and realistically the shower wont be pulling that (you could clamp it to see) therefor saying you should change the 6mm to 10mm is unneccessary (in my opinion). Doesn't matter that the MCB will take more than what it's rated at when the 9.5 kw shower wont be pulling more than the 40A

 

[sedgy34]

Until he resets the mcb.
strewth.

in his towel

 

[Guest55]

Agree with robd , as a fixed load , 9.5kw @ 230v pulls 41.3A
i wouldnt replace cable for an extra 1A for a few mins.

 

[Guest55]

in his towel

And that is an emergency that folk cant cope with ?

 

[SPARTYKUS]

....and if the owner accidentally leaves it on......... all day ......

Seen it!

Personally don't know enough detail about how (and if ) a shower left on "full" cycles (or not). Is it like a kettle, full tilt for the duration? I suspect not.

Dunno.

If in doubt change.

My gut tells me it might get warm but would be ok as long as PD matches CCC of cable.

 

[telectrix]

if it ain't broke, don't fix it. perfectly OK with a ccc of 47A on a 40A MCB.