faults, cables spur from mcb.

[optician]

Just so I've got it straight in my head, in this 32amp breaker you have both ends of a ring (2 cables 2.5mm) and then some one has also added a spur, another 2.5mm phase, 3 cables into one breaker?
If this is the case, the ring is protected by the breaker. the spur is not, 27amps max for 2.5mm.
Obviously if you have one socket you can only draw 13amps, two sockets and your close to fire with no chance of the mcb tripping? Am I thinking along the correct lines?

 

[hughesy]

It is absolutely fine to spur from the cu see pg 362 in your 17th edition regs if you dont have it maybe its time you updated.read the part about an unfused fuse spur.

Just so I've got it straight in my head, in this 32amp breaker you have both ends of a ring (2 cables 2.5mm) and then some one has also added a spur, another 2.5mm phase, 3 cables into one breaker?
If this is the case, the ring is protected by the breaker. the spur is not, 27amps max for 2.5mm.
Obviously if you have one socket you can only draw 13amps, two sockets and your close to fire with no chance of the mcb tripping? Am I thinking along the correct lines?

this is what they call diversity theres not a great chance it will draw 26a unless you used say 2 heaters and then the regs advise if you were to use electric heating you should wire a radial just for that and not put it on the ring as a ring in thefirst place is designed to share the load, its also the same with ceiling pendants technically th0.5 flex supplying the light is protected by a 5/6 or even a 10 amp fuse and we all know the smallest we can use is a 1.0mm but we also know a light bulb wont use that much current so diversity is applied.

 

[optician]

Thanks hughesy, have modified my thinking and read the page.

 

[hughesy]

Thanks hughesy, have modified my thinking and read the page.

No problem mate , im new to this site can you tell me how to raise a question , i know how to reply just cant figure out how to post a question. thanks.

 

[12345aob]

No problem mate , im new to this site can you tell me how to raise a question , i know how to reply just cant figure out how to post a question. thanks.

when you enter a section- scroll to the botton and click new thread. Hello btw.

 

[uksel]

you can have as many sockets in a radial circuit as you want

but any more than one s/o on the radial circuit you create then you need to protect the circuit by using fused spurs.

as for the disconnected phase being 'live' at 170v, this is very unusual. i'd unplug everything from the circuit (incase for some reason paranormal reason there is any abnormal capacitance, voltage sources like batteries there) i'd also disconnect and do some extensive IR tests to see if you've got any sort of leakage. i can say i've not come across anything like this before, except in emergency power/lighting supplies

let us know how you get on with this, i am intrigued

 

[KNIPEX]

hi thanks for the comments, it is on a lighting circuit, but the batt in em lighting should have nothing to do with it. this has never proved a prob before or on any other similar circuits in the building.

im looking into it and will let you all know