On the face of it i can't see why it would be coded at all. it's a poor design and could be inconvenient that's all.Might have been the only option when installed.  It obviously isn't overloading the fuse . There is no possible danger that i can see. At the very most C3.   Gary

An inspection on Friday saw a 200A switch fuse protecting a distribution circuit that supplies a busbar chamber that in turn supplies several more distribution circuits. Very common design approach. In terms of the concept, absolutely nothing wrong so unless there is something else in your situation that is causing concern, then it should not require a code. 
mind you, I do regularly see chaps giving code 2 for some reason where a protective device has more than one wire connected!

I agree - without some other damning factor you have failed to mention, it should be fine - how is the cable splitting done I presume not line taps flapping in free space ?

I'd push back for the reg no it contravenes, observing that you cannot find one.

Maybe post a photo if you are alllowed....

Mike.

If the lads undertaking these inspections had to set out a clear explanation of why they were issuing the code and the danger they perceive to be present, I suspect there wouldn’t be so many codes handed out! 

It seems a little odd. Let's say that each DB may draw up to 100A and ignore diversity. The fuse will need to be 200A and the "sub-main" rated accordingly. It may have been better to split (using Henley blocks, for example) earlier and have two switch fuses at 100 A each.

You have not mentioned whether these are SP or TP boards. If SP, a TPN switch-fuse could have been used.

Thanks for all the replies so far.....

So, some more detail....

The installation is commercial. The supply is 230/400V at 400A. After tariff metering, the supply passes through a main switch & into a 500A busbar chamber.

Connected to the busbars are around a dozen 3 phase switchfuses which supply various distribution boards around this small/medium sized factory.

The switchfuse in question contains 80A BS88 fuses and has two sets of 35mm^2 lugged onto each of the bolt-on lug terminals (one on the front, one on the rear). The submains are in SWA, glanded into trunking run above the switchfuses and each goes off to service a 12 way TPN board that supplies general light & power.  Although the boards are separate (by around 15m) they do service the same general area. There is no evidence of overloading or thermal distress in the BS88 fuses & the fuses have never blown. There are no heavy loads connected to either board - the biggest MCB present in either board being 32A TP (supplying ceeform sockets).

My thoughts are pretty much inline with you you are all saying: while perhaps not the best in terms of design it doesn't actually warrant a code at all.

I'm inclined to agree you Lyle, often, when challenged, the best answer they can give is "its illegal". Asking for a regulation which the tester feels has been broken isn't an unreasonable request.

Electrically what's there might be said to be equivalent to one cable supplying a single DB with twice as many outgoing ways - would anyone code for that?

   - Andy.

Exactly my thoughts, or even one supplying two DBs side-by-side.

No code from me!

Unconventional design perhaps, but not wholly uncommon.

Given that a C2 means 'Potentially Dangerous - Urgent remedial action required', in the absence of a declared regulation contravention perhaps the inspector would be able to provide an engineering reason as to how such danger may arise?  Assuming the 35mm submains are not buried in insulation and heavily grouped it would seem to be more than adequately protected by the 80A fuse.

I can't see that a code should apply.