MCB or MCCB?

[astormatt]

Afternoon all

Hopefully someone can throw some light on a small problem i have.
I am currently on a job, carrying out an eicr on a building and i am confused by the ocpd feeding it......
The set up is, main cut out in the sports hall building, then there are 5 circuits fed from the 200a main panel, this is where the theatre building i am testing is fed from.
The Zs at the 3 phase board is around 0.45.
The ocpd feeding it is branded OEZ and has C80 on it, which if you class it as a standard 60898 mcb would obviously put the Zs way above the max value. But as it's physical size is bigger than a standard 60898 3 phase mcb it has confused me, is it an mcb or mccb?
Google doesn't throw up much help so thought i would try here.

Thanks

Matt

View attachment 35493

View attachment 35494

 

[LeeH]

MCB or a high current version.

It's just a larger frame size

 

[Rocboni]

Usually 15ka BS EN60947-2?

What makes of distribution boards except these?

 

[LeeH]

Something like this I believe. I've fitted a couple of Chint 125A versions in control panels a few years back. Real chunky things but not a MCCB as far as I know.

Eaton MEM Memshield 3 High Load Capacity 1 and 3 Pole MCB's - Edwardes - https://www.edwardes.co.uk/en/categories/memshield-3-high-load-mcb-s-for-250a--b--boards-only

 

[LeeH]

Usually 15ka BS EN60947-2?

What makes of distribution boards except these?

Yep I'm wrong, here's the Chint one I was on about.

http://www.chint.co.uk/upload/product16.pdf

 

[Rocboni]

Link is to Eaton/Mem, all the brands do them, hager, schneider electric, chint, just I've never seen them refer to a panel which they actually fit in. Often seen them coupled to an RCD along side with a shunt trip

 

[LeeH]

Well, OEZ call them MCBs..

Data sheet here.

LST Miniature circuit breakers up to 125 A; 10 kA, OEZ s.r.o. - http://www.oez.com/products-profile/lst-miniature-circuit-breakers-up-to-125-a-10-ka-1

The LST model is a 60898.

 

[Rocboni]

Looks like they are only 10KA and still a 60898-1



http://www.oez.com/uploads/oez/files/ks/4307-z01-11_en_es_hu_pl_ro.pdf

 

[westward10]

If it has 60947-2 then it is not an mcb, if it has 60898 then mcb, well in my eyes anyway.

 

[astormatt]

Thanks all, yes that's it Rocboni, it does have 10kA on it.
I was 99% sure it was an mcb, but the size made me doubt myself.
Next job, what to do, to overcome the Zs problem.....
The install is only 5 years old so i wanted to see what they had put on their test certificate, as that is a big cock up in my opinion.

 

[LeeH]

Is it SWA?

 

[Wilko]

Hi - if I've understood correctly there is risk with ads now 10 seconds (say).

Edit : assuming not a design error, there will be a hot spot perhaps?

 

[westward10]

Thanks all, yes that's it Rocboni, it does have 10kA on it.
I was 99% sure it was an mcb, but the size made me doubt myself.
Next job, what to do, to overcome the Zs problem.....
The install is only 5 years old so i wanted to see what they had put on their test certificate, as that is a big cock up in my opinion.

Do you need to overcome the Zs problem if you are doing an EICR.

 

[astormatt]

Do you need to overcome the Zs problem if you are doing an EICR.

Yes as i am now main electrical contractor for the school.
Health and safety have been in, so the bursar wants every consumer unit tested and brought up to date if needed.

 

[astormatt]

Is it SWA?

Yes it is Lee, at a guess, minimum of 40m run mix of clipped direct and buried.

 

[The Ghost]

So what is that test button on it for ?

 

[Rocboni]

If it has 60947-2 then it is not an mcb, if it has 60898 then mcb, well in my eyes anyway.

Hagar appear to have there MCB (80-125A) as both 10 kA BS EN 60898-1 and 10 kA BS EN 60947-2

Matt, out of interest what type of panel is it, not that it matters, just interested?

 

[westward10]

So what is that test button on it for ?

I see no test button.

 

[Rocboni]

I see no test button.

Look above ( or to the side of) the red dot

 

[westward10]

Look above ( or to the side of) the red dot

I see now.