MEM mcb bs number

[Manator]

BS3871, 1965, withdrawn 1994, superceded,by BS en 60898 in 1991,and as far as I know all these were prior to the A,B,C classifications and used the numeric classifications of 1,2, 3.

 

[batty]

As this is an early MEM mcb i would put it down as BS3871 type 2 i think the confusion comes with the b at the end of the code i have a couple on both of them in small letters below the code it says type 2 maybe take another look i am sure you will find this is correct. If you take the MCB out of the consumer unit it has BS3871 on the side and duty cycle etc and in them days they were made in this great country.

 

[Nicky Tesla]

BS3871, 1965, withdrawn 1994, superceded,by BS en 60898 in 1991,and as far as I know all these were prior to the A,B,C classifications and used the numeric classifications of 1,2, 3.

I think you mean B, C, and D classifications.

There was a thread on here recently about putting terms down absolutely correctly and if anything even slightly wrong with those terms were written down, then the term was considered by many on here as nonsense. Now here we are willing to write on our test sheets that this MCB must be a type 2 even though it is not specified anywhere.

Another thing, we are willing to write down "not verified" on our test sheets when we do not know the rating of the mains fuse. This could be found out for sure by getting the supply guys to come down and take a look, but who the hell wants to do that?

The MCB and the mains fuse are both overcurrent protective devices and so should be treated in the same and not contradictory manner.

Suggestion...........why not put "not verified" in the type column (I know it w'ont fit in the box)

 

[marky1]

thanks for all your input gents

 

[Sidewinder]

ok great its a 3871 type B eh! type B , They dont exist, so have we really made any progress here?

Nicky Tesla,

Unfortunately you make incorrect statements once again.

I have uploaded a table from BS3871, I cannot upload much of the document as it is copyright, however, it goes to prove that you are once again incorrect with your information.

I do wish you would really understand things before you make rash statements.

You may well get yourself into trouble one day, if I am lucky I will be the expert witness who prepares the case against you!

 

[steptoe]

its an A

its there plain as day right after the 32,

 

[Doc Hudson]

Without getting to much into the debate, I would just add this link to a PDF that can be downloaded with a bit of brief information about low voltage circuit breaker standards. including BS EN 60898 (1991) & BS3871 (1965). Pages 8 & 9 have a some information about the instantaneous trip, time current characteristics, showing the key differences between Types B,C,D & 1,2,3,4. Hopefully it will show that '2' is not a direct comparision with 'B' and '3' is not a direct comparision with 'C'. As such, the importance of accuracy when using terminology and when identifying components of an electrical installtion should be clear to all electricians undertaking design or inspection work.

Guidance Documents

click on the link for:

Guide to low voltage circuit breaker standards. 1 Nov 09

Doc H.

 

[Sidewinder]

Quite Doc,

I have seen these documents before.

However, the table I posted is from 3871 which shows that both 1, 2, 3 & 4 along with B, C & D were available within that standard.

Hence why I feel that there is a lot of misinformation going on here again.

Unfortunately the BEAMA document does not deal with historic installs, which is what is at issue here.

 

[Doc Hudson]

Additionally it is an all to common mistake with untrained, unskilled, or those lacking competence, for electricians to just stick down any old number to fill in the boxes on a certificate or PIR. On a lot of domestic installations where final circuits are often no where near their maximum Zs limits, some consider it a non-critical piece of information. But if on a commercial or larger domestic installation for the safe operation of a protective device it becomes a bit important to know the correct types and operating characteristics. Far better to always ensure accuracy than to get into any bad habits of guessing.

Doc H.

---------- Post Auto-Merged at 21:56 ---------- Previous post was made at 21:48 ----------

Perhaps we can get a forum member to purchase a copy of the old BS3871 standard, only

 

[Sidewinder]

Doc,

This is the std I took the table from, I have limited access to certain BS's and this is one!

So, the table I have posted is the definitive one, I am not legally allowed to post the whole standard even if I could, which I don't think I can.

There may be another member who also has access to some BS's I'll ask him if he can verify my table if he has access to that particular standard if that is OK?

 

[kme]

I just have, and verify that 3871 does indeed have type b listed, as per the snake-hipped one`s post. opcorn

 

[Andy™]

your the only one thats failing here.

 

[Nicky Tesla]

[quote name='Andy

 

[Andy™]

thats not very constructive now is it? why are you giving abuse now? without proof its all just hot air

about as constructive as your posts.

 

[Nicky Tesla]

:CWOT STILL NO PROOF

 

[Andy™]

cant remember you offering any proof of your argument....

:C

oh thats right, you havent. probably because you cant find any

 

[Watchdog]

A timely reminder. ANY MEMBER WHO DIRECTLY INSULTS ANOTHER WILL HAVE THEIR POST REMOVED AND THEY WILL RECEIVE AN INFRACTION.

If this thread reads badly I have deleted 2 posts.

 

[Nicky Tesla]

[quote name='Andy

 

[kme]

I`ve seen a 3871 type B

The local ramada has a quite a few in the older square D boards.....

 

[batty]

Has Nicky got the sack he's gone a different colour.