Does this setup contravene any regs or is it ok?

[Ian1981]

Well an FCU contains an OCPD (Fuse).
If I use an FCU to spur off from a circuit, does the fact that there is an OCPD at the origin of the spur, make the spur a separate circuit?

Where does the supply originate from?
The circuits primary OCPD.
Why twist things and be argumentative as per?

 

[Deleted member 26818]

Why twist things and be argumentative as per?

It’s what I do.

 

[Deleted member 26818]

Sometimes, it actually makes people think.

 

[Ian1981]

It’s what I do.

Haha.
Yes you always provoke a response I’ll give you that.

 

[MFS Electrical]

Ok where’s the OCPD at the origin of an installation?

That depends on how far back to “origin” you want to go? The MCB is an OCPD if it’s an origin of a final CCT. The bs1361 or 88-3 fuse is An OCPD if it’s the origin of a particular installation. The substation fuse, the grids fusing all the way back to the OCPD at the generator...

 

[MFS Electrical]

deleted

 

[Deleted member 26818]

That depends on how far back to “origin” you want to go? The MCB is an OCPD if it’s an origin of a final CCT. The bs1361 or 88-3 fuse is An OCPD if it’s the origin of a particular installation. The substation fuse, the grids fusing all the way back to the OCPD at the generator...

The distribution network is outside of the scope of BS7671.
As the discussion is in relation to an Assessor stating something does not comply with BS7671, I was thinking of the origin as per BS7671.

 

[MFS Electrical]

The distribution network is outside of the scope of BS7671.
As the discussion is in relation to an Assessor stating something does not comply with BS7671, I was thinking of the origin as per BS7671.

That’s why I stuck origin in quotation marks in just playing devils advocate sarcastically I may add

 

[Silly Sausage]

Well an FCU contains an OCPD (Fuse).
If I use an FCU to spur off from a circuit, does the fact that there is an OCPD at the origin of the spur, make the spur a separate circuit?

That'll be a sub-circuit

 

[markythesparky]

I'm also interested in why markysparky disagreed with sparkychick's post re lollipop circuits.

Because, as Spin helpfully points out, details on how a circuit is formed is in appendix 15. And as we seem to be so intent on dissecting the regs to the nth degree, there is nothing at all that looks remotely like a ‘lollipop’ circuits in app15. Therefore, if it is not in the regulations of how a circuit should be wired, it is not compliant.

 

[markythesparky]

An OCPD cannot be the origin of a circuit, because BS7671 allows OCPDs to be omitted and also allows them to be positioned along the run of a conductor.

Which is exactly why my view is that the origin is the cable and where it connects to the OCPD.

 

[DPG]

The regs cannot possibly show every possible circuit. I presume you would class any lollipop ring you come across as unsatisfactory then?

 

[SparkyChick]

The Appendix 15 argument.

Appending 15 is informative only, it doesn't matter how many times people claim it is a regulation, it isn't, it's there in black and white (INFORMATIVE).

The opening text reads "This appendix sets out options for the design of ring and radial final circuits for household and similar premises in accordance with Regulation 433.1"

Options... it is not the exhaustive list of possibilities that comply with 433.1, if it were some of what we do everyday would be non-compliant (like a 20A DP switch feeding a single socket for an appliance wired in 2.5/1.5mm cable - complies with 433.1.204 but isn't on the diagram in appendix 15).

For a ring circuit to comply with the regulations, it must comply with 433.1.204 which defines the acceptable topology of a ring final circuit purely in terms of cable loading. Thus providing the cables are not overloaded in accordance with 433.1.204, a lollipop or ring final circuit will comply.

 

[markythesparky]

The regs cannot possibly show every possible circuit. I presume you would class any lollipop ring you come across as unsatisfactory then?

If course! A C3 if I were doing an EICR.

And how can it be a lollipop and also a ring? What would you put under the continuity tests in an EIC and also if the ‘stick’ end is of a larger size what size cable do you put in the EIC?

 

[markythesparky]

The regs cannot possibly show every possible circuit. I presume you would class any lollipop ring you come across as unsatisfactory then?

So you make your own up!

 

[SparkyChick]

If course! A C3 if I were doing an EICR.

And how can it be a lollipop and also a ring? What would you put under the continuity tests in an EIC?

Maybe the continuity of the conductors of the ring portion???

 

[markythesparky]

The Appendix 15 argument.

Appending 15 is informative only, it doesn't matter how many times people claim it is a regulation, it isn't, it's there in black and white (INFORMATIVE).

All the appendixes are informative with the exception of the appendix 1.

The opening text reads "This appendix sets out options for the design of ring and radial final circuits for household and similar premises in accordance with Regulation 433.1"

It sets out the ‘options’ by indicating what can be done and what is acceptable.

Options... it is not the exhaustive list of possibilities that comply with 433.1, if it were some of what we do everyday would be non-compliant (like a 20A DP switch feeding a single socket for an appliance wired in 2.5/1.5mm cable - complies with 433.1.204 but isn't on the diagram in appendix 15).

Where does it say that it’s not exhaustive?

For a ring circuit to comply with the regulations, it must comply with 433.1.204 which defines the acceptable topology of a ring final circuit purely in terms of cable loading. Thus providing the cables are not overloaded in accordance with 433.1.204, a lollipop or ring final circuit will comply.

I’ve said all through this thread ‘loads accepted’ or ‘loads considered’. Lets drop this part as I have accepted this. My argument is not about this, only the make up of a circuit and where it starts.

I have said on numerous occasions that two or more circuits that are lumped together in a protective device is not necessarily electrically unsafe, but just that it doesn’t comply.

 

[Deleted member 26818]

Yes Appendix 15 is informative.
It provides us with information.
It’s not the be all and end all, but there is no logical reason why the information provided should be ignored.
(Except of course when it states a Radial starts and finishes at the DB.)

 

[markythesparky]

Appending 15 is informative only, it doesn't matter how many times people claim it is a regulation, it isn't, it's there in black and white (INFORMATIVE).

All the appendixes are INFORMATIVE with the exception of app1.

The opening text reads "This appendix sets out options for the design of ring and radial final circuits for household and similar premises in accordance with Regulation 433.1"

It sets out the 'options' (something that may be chosen) of how to wire a type of circuit. It does not give 'examples' (one of a number of things or a part of something, an instance serving for illustration). If it could be wired like a lollipop it would have a diagrammatical representation of this too!

Options... it is not the exhaustive list of possibilities that comply with 433.1,

Where does it say that?

 

[DPG]

The regs can't possibly show every possible wiring configuration. And they don't need to - a competent electrician does not need to follow a guide covering every option. wiring installations can still comply with the regs even if they aren't specifically drawn in the book!