Shower EICR Code- 9.5kW- 40amp mcb!. De rate MCB to 32 or rewire cable to 10mm

[westward10]

Why just C2 it.

 

[CM 1]

Trying for a C3? It's either one code or the other!

We do over a thousand tests for local authorities and we can return a C3 as satisfactory with an advisory to rewire the shower as opposed to a C2 failure
It makes a big difference if we send back satisfactory cert! By the way the NICEIC say the 32amp MCB is a C3

 

[westward10]

I don't know why you are asking if you are already decided with "back up" from the brains trust.

 

[Ian1981]

I can't see how you can install a 32 amp mcb on a circuit designed to take around 40 amps.
By doing this and supplying a minor electrical works certificate or a EIC for the altered circuit it really doesn't comply does it?

 

[kingeri]

We do over a thousand tests for local authorities and we can return a C3 as satisfactory with an advisory to rewire the shower as opposed to a C2 failure
It makes a big difference if we send back satisfactory cert! By the way the NICEIC say the 32amp MCB is a C3

Ahh, sorry. I always thought that an EICR was a report on the condition of the installation, and the outcome is based solely on it's condition, not what we want the outcome to be.

 

[Wilko]

I attend a rental that some bright person has put a 10kW on a 6mm with 32A mcb. I have advised, but to no avail. I had a close look at the cable (bit I can see), mcb and shower connections and all seems ok, probably more due to use than good design. Strangely they have not asked me for a report .

 

[kingeri]

I attend a rental that some bright person has put a 10kW on a 6mm with 32A mcb. I have advised, but to no avail. I had a close look at the cable (bit I can see), mcb and shower connections and all seems ok, probably more due to use than good design. Strangely they have not asked me for a report .

Well it works, so what else matters?

 

[CM 1]

I don't know why you are asking if you are already decided with "back up" from the brains trust.

Wanted to see what others reckoned as many at our place don’t agree?

 

[KEV 1 N]

I'm surprised the local authority are not being more causious with this as its a potential fire hazard

 

[CM 1]

Well it works, so what else matters?

My own shower is a 9.5 kw on a 32 and 6.0mm , never trips no signs of damage , cable might be stressed but aren’t we all?

 

[CM 1]

I'm surprised the local authority are not being more causious with this as its a potential fire hazard

They believe it should be a C3

 

[CM 1]

The problem here is the short time the shower operates for,
Years ago our company added lots of heaters to a ring main in a school, despite me protesting as the QS that it was non compliant, and should be on a dedicated ring or radial circuits, every winter the circuit would trip after about 6 hours , I calculated there was a load of 4 x 12 Amps = 48 amps plus other stuff on the ring yet took 6 hours to trip on a 32amp ring !

 

[Ian1981]

I2 must be equal to or less than 1.45 x Iz so what are you actually basing Iz as?

 

[Leesparkykent]

The 32amp mcb will likely trip on overload as 9.5kw is 39amps at 240v or 41amps at 230v. Advise a down rate size of shower to suit cable or they need to upgrade it to 10mm2 for the 9.5kw
Is there any signs of over heating at all the terminals?

If the shower is rated 9.5KW at 240V then at 230V it's 38A.

 

[CM 1]

If the shower is rated 9.5KW at 240V then at 230V it's 38A.

Yes but a 32 amp mcb will take that for an hour plus

 

[Leesparkykent]

Yes but a 32 amp mcb will take that for an hour plus

So what? It's still wrong isn't it....IMO it's simple, no code if the CCC based on design current is adequate taking installation method in to account. Code 2 if the CCC based on design current isn't adequate taking installation method in to account.

 

[buzzlightyear]

My own shower is a 9.5 kw on a 32 and 6.0mm , never trips no signs of damage , cable might be stressed but aren’t we all?

If the shower is rated 9.5KW at 240V then at 230V it's 38A.

I total agree with you leesparky
why post a question on here if you know the answer. not!

 

[buzzlightyear]

well .you may has well put the shower on bell wire .and see what you get!

 

[Wilko]

Just looking at some ABB reference info on BS 60898 - it says the mcb must not trip before 1.13 times it's rating and must trip at 1.45 within an hour (if I'm reading it right).
So the OCPD may not be protecting the cable from sustained overloads less than 1.45, which is probably why Ib < In < Iz is drummed into us
https://library.e.abb.com/public/114371fcc8e0456096db42d614bead67/2CDC400002D0201_view.pdf

 

[CM 1]

well .you may has well put the shower on bell wire .and see what you get!