Interchangeable MCB'S RCD'S Etc ( What Fits? )

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If manufactures original parts are available I doubt any competent electrician would choose to fit other manufactures parts. However we sometimes have to make a considered judgment over what is best for the customer..
I keep finding dorman smith and merlin gerin boards with hager MCBs stuck in them (and occasionly wylex and proteus as well), I hate it, its just lazyness, can't be bothered to order the right breaker..

If its older equipment then I have done it on a time or two, but usually can find one thats been removed from a board change thats right for the board

 
The only reason manufacturers state you must not mix and match is because they want to sell you a whole new consumer unit. Think about it, what about when you purchase a separate enclosure and then an RCD with some breakers and the enclosure is a different make, would you worry? Something is very wrong in the world today.

 
Just reading through this thread and there appears to be mixed opinions and ideas regarding mix'n'matching Single pole device's on CU's, well interestingly enough I just had my recent NAPIT field inspection and we got on to the subject of CU layouts and his words word that of advocating installing a well branded make such as MK board & main switch coupled with e.g all Volex RCBO's.

We discussed this a little and his argument was that all RCBO's/MCB's etc. are all tested to a BS EN Standard so as long as it fits correctly then it should be satisfactory and the cheaper branded RCBO prices keeps the client happy with a realistic invoice amount.

BTW....I'm not suggesting that the above mentioned equipment will match but merely used as an example and will not be responsible for the masses rushing down to there local CEF to snap up all the MK bare bones and Volex Single pole device's..... :run

Regards,

Mac

 
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Welcome to the forum Mac. These are my thoughts also. I generally use TD line ones in MK consumer units as these are half the price of MK and actually look identical apart from the writing. The TD line consumer units I find a bit flimsy so that is why I tend to use MK. I have also used forum sponsor ones which also fit perfectly. Manufacturers will prefer you to use only there equipment as they want all the profit.

 
I read in the electricians wives magazine you get for free in the wholesalers, thats there frowning on us mixing and matching mcbs in a d.b,tut tut

 
Hi,

Just thought i'd add wylex is pretty much direct swap for abb, little tight but no altering needed (which i think is a defo no no, it fits or it don't)

Will own up to a little bit of buz bar bending on occassion, but that hasn't changed anything that would compromise the mcb. Filing the buz bar prongs down i would say is leaving yourself wide open if something went wrong (changing the fundamental design). I know in the real world that it probably won't, as they are more than big enough to carry the loadings.

As for the debate, i think its not good practise (they look nicer when all matching), but on domestic will do it without much sleep lost. Do try not to though, but in my eyes not worth the costs of an extra visit. Don't do it on commercial jobs unless its a have to.

 
In the latest NICEIC mag, there is an article on this. Their view is that it should not be done unless manufacturers of both types of MCB confirm that they are compatible. They claim there may be an overheating issue. Sounds like doggy doo doo to me but it raises the question about what the inspector would say I saw that you had done it on a job he was looking at. Classic case of pen pushers looking for something else to balls up? How would you prove it was safe if you ever ended up in court because something happened at the install address?

 
Other than fitting Crabtree/Wylex/Steeple/Volex I'd say that its highly unlikely that anything untoward will ever occur.

However , now the suits have made it a big issue we all have to address it .

Like someone said :-

What if you mixed a Bill Talisman ,an MEM and an Eaton in a board ?. They are all made by the same firm and are replacements for each other . An old bord full of Talismans will accept either of the other two .

---------- Post Auto-Merged at 21:30 ---------- Previous post was made at 21:26 ----------

Is anyone taking Electrium to task for supplying MCBs that melt while in use , I wonder .

It would have been a much safer job if the sparks had shoehorned a couple of Hagers in their place , methinks!!!

 
Just thumbing through the Toolstation catalogue today and found some GE plug in breakers [forgotten all about them]...so whats all that about?

As far as I know the only boards that these will fit are Wylex and Proteus, and to the best of my knowledge GE do not make a board that will accept these breakers,

So does that meaan it is ok to use them in others' boards and if so where is the bit of paper that says so? OR if they are not ok then why do they make them? Discuss; (20 marks) ..................... :coat

 
l have to replace a hager 63a 30m/a R.C.D. for a hundred amp, will a Wylex ( or other ) fit ?

 
heres a question for you lads, i have ordered a one electrical 100ma rcd and need an mcb to fit rated 50a tyoe b does anyone know which make fits with this rcd as both are supplying power to an office building and garden shed setup. and by the way its tns supply ;)

 
I haven't got one here to look at right now, but with the Square D SQO type breakers they look like they might actually be a standard breaker with a screwed in section for the shielded busbar which I have seen done with another type I cant recall

You may find that if you removed the plastic shroud covering the top section you would just find a screw like on a normal breaker

I will actually be swapping one out later for a 40A, so when I get the 16A its replacing back home I might have a play and see if that is the case

 
the Square D SQO type breakers they look like they might actually be a standard breaker with a screwed in section for the shielded busbar


They are.

You may find that if you removed the plastic shroud covering the top section you would just find a screw like on a normal breaker


You do.

Welcome to 20 years ago!

 
I think mixing breaker makes, assuming they will fit properly is down to common sense and judgement, suppose you had a large 3 phase board in a factory, and they needed a new 6A circuit for a couple of outside lights. Now if you were unable to obtain that make of breaker because say it was an obsolete board then you are left with only 2 options, either fit a breaker of a different make, that fits securely and is suitable for the application, kA rating etc. Or option 2,which involves replacing the whole board, this is going to be, more expensive, and will either involve a shutdown of some sort or mean waiting until the normal shutdown occurs. Given the increased costs these days how many factory owners are going to be happy when a job costing say 2 or 3 hundred quid suddenly escalates to over a thousand.  

 
if you were unable to obtain that make of breaker because say it was an obsolete board then you are left with only 2 options


3 actually, use an existing circuit. Either a 6A circuit to connect the lights to directly, a <32A circuit and connect a switch fuse or find a spare circuit (or make one) and stick another board as a sub off the existing.

 
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