More than one circuit on breaker

[Richard3009]

I have found in my house on the downstairs ring main that three lives are terminated into the 32A circuit breaker, two are for the ring main as you would expect; the third is for a socket below the fuseboard, to all intents and purposes its just a spur and electrically wise its sound.
Just wondered how this stands up with regs having three conductors in the breaker.

 

[wet string]

my understanding of the regs, from memory mind, is that a spur can originate from a termination at a socket outlet, a junction box or at the origin of the circuit.

 

[Stixicus]

yes, would agree with wetstring - it is acceptable to have a spur on the circuit from the consumer unit in this way.
Never done it on sockets, but it is a good way of adding an outside light on a lighting circuit if there are no spare "ways" in the consumer unit.

 

[flukey]

would agree with the other replies if all the cable calcs work out.

what size cable is supplying the single socket??

 

[Richard3009]

2.5mm T/E

 

[flukey]

then i would see that individual socket as more of a radial being served directly from the breaker in this way and i wouldnt have a 32 amp radial on a 2.5 t/e

 

[Richard3009]

why?????? maximum load 26A no different to a spur,

 

[flukey]

if i was designing a circuit being fed from an mcb directly to a socket irrespective of what other cables were in the mcb already i would see that circuit as a radial, not a spur.
26a cable and 32a breaker .
i see where your coming from spurring from existing socket etc etc but not from board.
just my opinion

 

[Richard3009]

the regs permit it, any spur is a single 2.5mm cable protected with 32A breaker

 

[kevinreilly]

on rings not radials

 

[Tiger]

the regs permit it,

Where, my book says it should be protected by 20amp

 

[flukey]

just looking it up.
what reg number you got

 

[Tiger]

page 363

 

[Richard3009]

its not a radial, you can't have more than one double 13A on it, a radial you can providing the conductor size is correct for the potential load.

 

[flukey]

didnt mean you tiger, was asking richard.

dont forget Ib has to be equal to or greater than In when selecting a cable richard.

point me to the correct reg and i will stand corrected

 

[Richard3009]

so based on this you cant spur from the breaker itself

 

[Spudnik]

If there was a radial circuit from a 20A MCB then thats fine

If there was a "spur" from a 32A RFC MCB then that is also fine.

It is no different at all to taking a spur off the back of a socket or at any point in the ring via jb.

Pg 362/3

 

[wet string]

the spur should only feed one outletunless fed through 13afcu so max current via 13amp plugs, 26amps.

 

[Richard3009]

If there was a radial circuit from a 20A MCB then thats fine

If there was a "spur" from a 32A RFC MCB then that is also fine.

It is no different at all to taking a spur off the back of a socket or at any point in the ring via jb.

Pg 362/3

Correct

 

[Tiger]

yougot aproblem withyour keyboard