Mix & match mcb`s

[Sidewinder]

What about this from a place in the middle of London.Durham

switchgear boards butchered with a grinder to accept memshield (1) MCBs and bits of Perspex bolted on to cover unused ways?

since I started doing work for them we have been discussing the possibility of replacing the boards, but it's a bit of an elephant in the room, we all know it isn't exactly great but nobody wants to drop a bombshell on the people who hold the purse strings. 

So the boards are slowly becoming surrounded by extra enclosures for the RCDs which are being added to circuits as and when it becomes necessary. 

So the "persons unknown" who have done this, have they even considered the requirements of BS6423?

 

[Sharpend]

I don't believe the nic preach this bs6423 to their 5ww's. ??

 

[Davethsparky]

So the "persons unknown" who have done this, have they even considered the requirements of BS6423?

I don't think they are quite as unknown as all that actually, I believe the person who will ultimately be signing the order to replace the DB's may have been at least passing the tools to the person doing the job if not more involved. 

Of course they haven't considered anything to do with regulations. 

This was all done within a year or two of the boards being fitted around 25 years ago as a knee jerk reaction to a couple of the original mcbs becoming faulty.  

 

[Nebakineza]

The BS number regarding MCB's is just to identify them to a particular standard. MCBs will differ in design, fitting different boards yet will always have the BS 60898 as that is there standard identification in Britain. I'm sure MCB's are now a BSEN60898 European standard now. Point being however, is that matching the BS number does not guarantee than an MCB will fit the same board as another due to the fact that it is only a reference.

Cheers and take care.

 

[kerching]

And this gobbitt of information from the NICEICs seldomly asked "questions from the hot line"

Darren's Frequently Asked Questions

Question:

Can I install a different make MCB in a different manufacturer’s distribution board?

Answer:

Generally not. Manufacturers’ instructions for consumer units and distribution boards typically advise against this for technical reasons, such as overheating. Equipment from other manufacturers should not be mixed unless documentation is obtained from the manufacturer of the consumer unit or distribution board confirming that the specific mixed arrangement is suitable for use.

 

[ProDave]

The BS number regarding MCB's is just to identify them to a particular standard. MCBs will differ in design, fitting different boards yet will always have the BS 60898 as that is there standard identification in Britain. I'm sure MCB's are now a BSEN60898 European standard now. Point being however, is that matching the BS number does not guarantee than an MCB will fit the same board as another due to the fact that it is only a reference.

Cheers and take care.

And we have this mess because BSEN60898 might say some things about an MCB, but it does NOT state the physical dimensions accurately, hence we have the sutuations where mcb's to the "same" spec are physically different.

Just typical of the electrical industry though.

 

[NozSpark]

And we have this mess because BSEN60898 might say some things about an MCB, but it does NOT state the physical dimensions accurately, hence we have the sutuations where mcb's to the "same" spec are physically different.

Just typical of the electrical industry though.

That's just product protection...

 

[binky]

but given the amount of 'badge engineered' products, ie same factory different labels, that is a bit of a non-sense more to do with bottom protection than technical reasons.

 

[Nebakineza]

And we have this mess because BSEN60898 might say some things about an MCB, but it does NOT state the physical dimensions accurately, hence we have the sutuations where mcb's to the "same" spec are physically different.

Just typical of the electrical industry though.

You're right, it would make a lot of sense to standardise the dimensions a long with the performance. It would play havoc from a branding point of view however. Money, money, money...

 

[SPECIAL LOCATION]

MCB's should be the same as cartridge fuses or fuse wire  IMHO....

standard set of operating characteristics and dimensions so all manufactures to that standard are interchangeable!

that would bring down the price of MCB's & RCBO's with some full competition between all manufacturers.

Guinness