need some advice re current CU

[ianphilip007]

hi there

i currently have a 6 way wylex NN board which has a 63A BS4293 RCD main switch. The MCB's are BS3871 Type 2 and 3.

would any new circuit added to this board be non compliant ? and therefore fail a Elecsa or any competent person assessment?

basically does the board need to be changed before i can add new circuits ?

many thanks

 

[ianphilip007]

thinking the 4293 rcd and the 3871 mcbs are now obsolete am i correct ?

 

[SPARTYKUS]

Does the RCD operate correctly at x1 and x5, and ramp test. Is it a 30mA RCD.

They're not manufactured any more but that doesn't mean they aren't fit to work!

Confirm the RCD works with an RCD tester.

Do you mean you have space on that old board and want to add an old MCB to it?

 

[Electro-tech]

Save the hassle and change the board.The RCD is 100ma.

 

[malcolmsanford]

Save the hassle and change the board.The RCD is only 100ma.

As the OP edited the thread where did the 100mA come from Tech

 

[ianphilip007]

rcd is not 100ma it is 30ma and yes its trip time at x1 and times 5 are within spec. Ramp test is fine too.

i have a spare way with an exisiting 30Amcb in the exisiting board and wanted to run a new circuit.

 

[ianphilip007]

again want to use for assessment so dont want to fail because the mcb/rcd are obsolete.

 

[Electro-tech]

Save the hassle and change the board.The RCD is 100ma.

Sorry Guys gone totally mad today ! Need Medication.

 

[tony mc]

I can't see any reason for not adding a new circuit to the existing board as long the RCD is still operating correctly like you have said.

SPARTYCUS has highlighted the obsolete bit.

Dont forget your bonding etc and highlight on the EIC re the main switch (RCD)covering the entire installation (Cant think of the word I am looking for)

 

[ianphilip007]

Limitation ? or may be a deviation from reg 513. ? really dont know if i should change the board ? if it were not to be assessed by elecsa i think it would be fine. any opinions ?

 

[ianphilip007]

just want it to be right for assessment and have these niggling little problems that i know my self are not ideal ie (rcd main switch and the old nature of the rcd and mcb) evrything else is to the 17th its just a pretty important part mainly fault protection and rcd protection thats not ideal. now if i note the niggles as limitations or deviations from BS7671 is this enough just dont want to fail due to niggles that i know are there.

 

[tony mc]

Sorry you have lost me with 513 Accessibility. LIM is for PIR' s only!

It should make no difference if it is you assessement just make sure all the work you do is per the regs and you will have no problems at all!

 

[Big n Daft]

If it tests ok, then it is ok.
Just note the limitations.

 

[ianphilip007]

sorry wrong number lol was referring to segregation of circuits . so with the rcd mainswitch, and the older mcb's i will meet 17th edition criteria.

 

[ianphilip007]

if thts the case then ill leave the old board and save some notes. all disconnection times and zs values will be met and if i can note the limitation that will be cool

 

[ianphilip007]

thanks for all replys

 

[SPARTYKUS]

T'was a good question ian

 

[ianphilip007]

any more thoughts ?

 

[colshaws]

Are you already an Elecsa member or is it your first assesment, if already a member phone their Tec line , the guys there will steer you the right way.

 

[Octopus]

If you're not a member yet and are thinking of using it for your assessment, I'd recommend calling Elecsa and running it past them.

They don't bite and I always find them helpful.