BS3036 Breaking Capacity

[NickD]

I know this has been asked before but I can't locate a thread with a conclusive satisfactory answer...

Got an old Memera 3 board (says it's to BS5486 Pt.13) with a mix of BS1361 cartridge and BS3036 rewireables. PFC is 2.03kA. Breaking capacity of BS3036 may be 1/2/4kA depending on type (S1A/S2A/S4A), but I can't get any clarity on what the type means or how to tell what ones are present here so I have to assume 1kA. Upstream DNO fuse is stated as BS1361 60A type 2 which has 33kA breaking capacity (which I have no desire to rely upon).

So unless someone can tell me a way to honestly declare these BS3036s are S4As, I have an issue with breaking capacity < max PFC. However, I have a recollection of reading something somewhere which says that the breaking capacity can be that conveyed by the overall board enclosure rating, so does the board being BS5486 Pt.13 help me here? Can't locate it in BS7671 (and not sure it was in there anyway).

Advice much appreciated.

 

[Clive P]

Hi Nick,

From memory, the problem that arises with 3036 rewirables is the time/current characteristics ( Appendix 3 ). Although the PSSC can be handled by the BS1361 Type 2 ( 33kA ), but as you say I wouldn't want to rely on this as the sole protection. No doubt there will be somebody on here who will be able to supply you with all the information, maybe Tony; I expect he invented them ( no malice intended ).

Regards.

 

[NickD]

maybe Tony; I expect he invented them

Harsh

 

[Clive P]

Hi,

Not meant to be, thought it might wake him up from his afternoon slumber,

Regards.

 

[hillbillie]

Guidance note 3 says, on page 54, that you can take the s/c capacity of the fuses to be 16KA when:
the current ratings of the devices don't exceed 50A
The d/b is a 5486-13 or better
it is supplied through a type 2 BS1361 fuse rated at no more than 100A

I assume then that the BS 1361 will turn into a lump of glass after 2KA goes through it

 

[Lucien Nunes]

Have you tried Eaton MEM technical? They did help me out with an enquiry about some old gear in the past, perhaps they still have specs on file somewhere? Alternatively, perhaps you could sidestep the issue by dropping HRC carriers and shields into the ways currently protected by rewireables?

 

[NickD]

Guidance note 3 says, on page 54, that you can take the s/c capacity of the fuses to be 16KA when:
the current ratings of the devices don't exceed 50A

YES!!!! That's the paragraph I remember. We must be on different versions of GN3 cos mine's on p.57 and says "Where a service cut-out containing a cartridge fuse to BS 88-3 (formerly BS1361) supplies a CU which complies with BS5486-13 or BSEN60439-3 Annex ZA, then the s/c capacity of the OCPDs within CUs may be taken to be 16kA".

I love you hillbillie, and I want to have your babies.

 

[Guest111]

this may help

www.voltimum.co.uk/files/gb/others/...Tech_Manual_Fuses.pdf

 

[NickD]

perhaps you could sidestep the issue by dropping HRC carriers and shields into the ways currently protected by rewireables?

Considered it. It's not ideal having a mix (including at the same rating, 30A 3036s and 1361s both present and interchangeable - which have slightly different max Zs for 0.4 disconnection time, for a start, which is worrying, fortunately all relevant circuits have Zs well below the lower of the two figures) and rewireables are a potential nightmare anyway. Would cost the client about £40 for used ones off eBay (which brings its own risk to me), doubt they'd go for it.

 

[NickD]

www.voltimum.co.uk/files/gb/others/...Tech_Manual_Fuses.pdf

It's dead Jim, dead Jim, dead.

 

[Guest111]

It's dead Jim, dead Jim, dead.

pm me your email and i'll send it to you

 

[shanky887614]

this may help

www.voltimum.co.uk/files/gb/others/...Tech_Manual_Fuses.pdf

misssing part of link

If its not blue its not part of the hyperlink

 

[Hawkmoon]

Funny how the onsite guide makes reference to a fuse (dno) that we can't actually open up and look at...

Snip, Snip - 'I saw no seal'

 

[NickD]

Ridiculous isn't it? You potentially can't complete an EIC or EICR without knowledge of the DNO cutout fuse type/rating, but legally you can't pull it to see.

 

[MDJ]

I know this has been asked before but I can't locate a thread with a conclusive satisfactory answer...

Got an old Memera 3 board (says it's to BS5486 Pt.13) with a mix of BS1361 cartridge and BS3036 rewireables. PFC is 2.03kA. Breaking capacity of BS3036 may be 1/2/4kA depending on type (S1A/S2A/S4A), but I can't get any clarity on what the type means or how to tell what ones are present here so I have to assume 1kA. Upstream DNO fuse is stated as BS1361 60A type 2 which has 33kA breaking capacity (which I have no desire to rely upon).

So unless someone can tell me a way to honestly declare these BS3036s are S4As, I have an issue with breaking capacity < max PFC. However, I have a recollection of reading something somewhere which says that the breaking capacity can be that conveyed by the overall board enclosure rating, so does the board being BS5486 Pt.13 help me here? Can't locate it in BS7671 (and not sure it was in there anyway).

Advice much appreciated.

16ka is standard