Spur off 32a house socket form garage for 20a supply.

[MDJ]

No, you can't take a distribution circuit (submain) from a final circuit.

nothing else to say, this is the answer, end of

 

[loz2754]

The IET doesn't seem to agree with that sentiment, and suggest connecting equipment via a 16A breaker in the OSG. This is from appendix H, P211:

Permanently connected equipment should be locally protected by a fuse complying with BS 1362 of rating not exceeding 13 A or by a circuit-breaker of rating not exceeding 16 A and should be controlled by a switch, where needed (see Appendix J).

Note that this refers to permanently connected equipment (for which the load would be known and fixed). This would not allow for connecting socket outlets or another consumer unit, for which the load is obviously not known nor fixed.

Of course, this appendix is dealing with standard (formerly known as conventional) final circuits.
There is nothing to stop a competent designer from doing whatever they want, as long they note it as a deviation on the certification, and declare that it is no less safe than it would be if the design was done strictly to BS7671.

 

[mainline]

Permanently connected equipment may be connected directly to a ring final circuit using a fused connection unit incorporating a BS 1362 fuse (not exceeding 13 A) or a Type B or C circuit-breaker (not exceeding 16 A) complying with BS EN 60898 or BS EN 61009-1, or BS EN 60947-2. In the case of some existing installations, Type 1, 2 or 3 MCBs complying with BS 3871 may still be encountered.

 

[mainline]

The OP asked if he was "allowed" to take use 16A or 20A protection from an unspecified device to give himself an extra 3kW on a garage supply. The OP stated that their intention was to do so by "spurring" this unspecified protective device off a ring final circuit in place of a fcu. Her went on to clarify that this would supply 16A & 6A RCBOs in the garage.

You responded by stating that "he could".

These are the facts and let's not dress it up by claiming any information beyond that posted.

The advice wasn't in line with regulatory requirements and has the potential for loads considerably above that permitted to be carried by the cable intended for use if 20A protection is used at the proposed 'spur'.

Edit: I'm not the forum police and you're free to post as you please. On this occasion I believe the advice to be inappropriate and challenged it.

@westward10 asked him to clarify as to what he was actually wanting my answer was in response to the Ops post hence is why I quoted the Ops post in my one with yes he can.

 

[mainline]

Note that this refers to permanently connected equipment (for which the load would be known and fixed). This would not allow for connecting socket outlets or another consumer unit, for which the load is obviously not known nor fixed.

Of course, this appendix is dealing with standard (formerly known as conventional) final circuits.
There is nothing to stop a competent designer from doing whatever they want, as long they note it as a deviation on the certification, and declare that it is no less safe than it would be if the design was done strictly to BS7671.

The max load of the entire circuit is still governed by the 32amp breaker.

 

[nicebutdim]

@westward10 asked him to clarify as to what he was actually wanting my answer was in response to the Ops post hence is why I quoted the Ops post in my one with yes he can.

I know and it was this I challenged. Nothing has yet supported your position that the proposed '16A or 20A spur' is acceptable.

 

[nicebutdim]

The max load of the entire circuit is still governed by the 32amp breaker.

Governed to what level of overcurrent?

A downstream type B 20A mcb could allow more than 32A for a considerable period of time on the proposed spur, without tripping. Not sure 32A protection at source is going to do much.

 

[mainline]

Governed to what level of overcurrent?

A downstream type B 20A mcb could allow more than 32A for a considerable period of time on the proposed spur, without tripping. Not sure 32A protection at source is going to do much.

How different would it be if the ring was extended, which I assume you would agree was ok ?

A double socket outlet could have a 26 amp load, but one that has 16amp load would be too much ?

 

[Pretty Mouth]

Note that this refers to permanently connected equipment (for which the load would be known and fixed). This would not allow for connecting socket outlets or another consumer unit, for which the load is obviously not known nor fixed.

Of course, this appendix is dealing with standard (formerly known as conventional) final circuits.
There is nothing to stop a competent designer from doing whatever they want, as long they note it as a deviation on the certification, and declare that it is no less safe than it would be if the design was done strictly to BS7671.

It refers to permanently connected equipment, not specifically permanently connected current-using equipment.

Electrical equipment (abbr: Equipment). Any item for such purposes as generation, conversion, transmission, distribution or utilization of electrical energy, such as machines, transformers, apparatus, measuring instruments, protective devices, wiring systems, accessories, appliances and luminaires.

Current-using equipment. Equipment which converts electrical energy into another form of energy, such as light, heat or motive power.

 

[nicebutdim]

How different would it be if the ring was extended, which I assume you would agree was ok ?

A double socket outlet could have a 26 amp load, but one that has 16amp load would be too much ?

Again that's not in line with OP's proposal of 16A or 20A protection.

You're here in your capacity as an electrician providing advice. What might or might not be okay is of less relevance than what regulations permit.

People often come here and listen only to points which suit their thinking. As such I'm of the opinion that advice to DIY members shouldn't play fast and loose with regulations. On this occasion the OP declined the opportunity to provide any information about experience or qualifications, so should be treated as being entirely without either.

 

[mainline]

Again that's not in line with OP's proposal of 16A or 20A protection.

You're here in your capacity as an electrician providing advice. What might or might not be okay is of less relevance than what regulations permit.

People often come here and listen only to points which suit their thinking. As such I'm of the opinion that advice to DIY members shouldn't play fast and loose with regulations. On this occasion the OP declined the opportunity to provide any information about experience or qualifications, so should be treated as being entirely without either.

The OP asked a simple question, "Could he achieve a bigger supply to a garage of 16 to 20amps, rather than the 13amp Fcu that he has.

And the answer is : Yes he can
He can do that by simply extending the ring.
So the answer i gave is correct.

 

[mainline]

I know and it was this I challenged. Nothing has yet supported your position that the proposed '16A or 20A spur' is acceptable.

Permanently connected equipment may be connected directly to a ring final circuit using a fused connection unit incorporating a BS 1362 fuse (not exceeding 13 A) or a Type B or C circuit-breaker (not exceeding 16 A) complying with BS EN 60898 or BS EN 61009-1, or BS EN 60947-2. In the case of some existing installations, Type 1, 2 or 3 MCBs complying with BS 3871 may still be encountered.

 

[mainline]

The OP asked if he was "allowed" to take use 16A or 20A protection from an unspecified device to give himself an extra 3kW on a garage supply. The OP stated that their intention was to do so by "spurring" this unspecified protective device off a ring final circuit in place of a fcu. Her went on to clarify that this would supply 16A & 6A RCBOs in the garage.

You responded by stating that "he could".

No I didn't my response was to a later clarified by the OP post, I have now said this a number of times, but you seem to be ignoring it.

 

[nicebutdim]

The OP asked a simple question, "Could he achieve a bigger supply to a garage of 16 to 20amps, rather than the 13amp Fcu that he has.

And the answer is : Yes he can
He can do that by simply extending the ring.
So the answer i gave is correct.

Again we seem to be skipping inconvenient detail.

The OP specifically asked 'is this allowed?" Maybe you thought he was asking if you allowed it, but I think most people would understand the question was specifically about what the Wiring Regulations might make of the proposal.

 

[mainline]

Again we seem to be skipping inconvenient detail.

The OP specifically asked 'is this allowed?" Maybe you thought he was asking if you allowed it, but I think most people would understand the question was specifically about what the Wiring Regulations might make of the proposal.

Extending the ring is allowed.

And so is:
Permanently connected equipment may be connected directly to a ring final circuit using a fused connection unit incorporating a BS 1362 fuse (not exceeding 13 A) or a Type B or C circuit-breaker (not exceeding 16 A) complying with BS EN 60898 or BS EN 61009-1, or BS EN 60947-2. In the case of some existing installations, Type 1, 2 or 3 MCBs complying with BS 3871 may still be encountered.

 

[nicebutdim]

Permanently connected equipment may be connected directly to a ring final circuit using a fused connection unit incorporating a BS 1362 fuse (not exceeding 13 A) or a Type B or C circuit-breaker (not exceeding 16 A) complying with BS EN 60898 or BS EN 61009-1, or BS EN 60947-2. In the case of some existing installations, Type 1, 2 or 3 MCBs complying with BS 3871 may still be encountered.

Leaving to one side any argument over how 'permanently connected equipment' should be defined, as I feel we're going to be of differing opinion on that, your post actually undermines the point you've been trying to defend.

You gave the nod to a "16A or 20A supply" which is at odds with what you've quoted above.

 

[nicebutdim]

No I didn't my response was to a later clarified by the OP post, I have now said this a number of times, but you seem to be ignoring it.

This clarified post or another that no one else can see?

Apologies. My mission is to achieve a bigger supply to a garage of 16 to 20amps, rather than 13a. I'm not trying to achieve anything physically, I just want to know if it's possible, forgetting about what the spec is for the job. Is it allowed?

I'm not going to waste time repeating point which I've already made.

 

[nicebutdim]

Extending the ring is allowed.

OP's proposal never involved extending an RFC.

Don't make stuff up.

 

[mainline]

OP's proposal never involved extending an RFC.

And ?

OP :My mission is to achieve a bigger supply to a garage of 16 to 20amps, rather than 13a. I'm not trying to achieve anything physically, I just want to know if it's possible, forgetting about what the spec is for the job. Is it allowed?

And I said yes you can

This can be done by extending the ring, is this not correct

 

[nicebutdim]

This is the post I challenged, quoted below in its full glorious brevity.

Yes you could

You clearly feel it was an appropriate response to the OP's question or, more specifically, his later clarification.

I'm of a different opinion and no amount of arguing or attempting to change the facts is going to change that.

Feel free to continuing this argument as a solo endeavour as I've nothing more to add in response to you original comment, subsequent attempts at justifcation of it or defelction in various directions from it.

I've stated my case quite clearly. Several times.