So what about the old wooden back frame CU? Yes/No/Don't Know?

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In our little 'real world bonding thread' the point about the old wylex CU with a wooden back was mentioned....

{ have a read of this thread if you haven't already look at it...

http://www.talk.electricianforum.co.uk/showthread.php?t=1377 }

So as there seemed to be a bit of interest from those guys interested in 2391 I&T....

Lets have another look at the CU... does this comply OR not?

what observations could be made about this fusebox?

Try & justify with appropriate regs or guidance notes?

Here's the CU picture again

A few facts need to know..

4 circuits..

1 x 5amp radial lighting u/s 1.0mm

1 x 5amp radial lighting d/s 1.0mm

1 x 30amp ring sockets u/s & d/s 2.5mm

1 x 30amp radial old cooker (now 3 sockets & FCU in kitchen) 6.0mm

NO electric shower OR electric over/hob/cooker.

[*edit*] NO immersion Heater [*edit*]

Total load should not be any problem with this 4-way CU

e.g. simple diversity calc 100% biggest circuit 40% remaining circuits 30 + (40x0.4)= approx 46amps.

All fuses are semi-enclosed BS3036 re-wireable.

from previous thread we know 6.0mm main bond to Gas & Water

16mm incoming tails

6mm incomming from MET to CU earth bar.

PME earth arrangement (TNCS).

well there you go..

Discuss?.... ?:|

(my money's on the VET getting it all spot on!! ; \ ;) :eek: :^O:^O:^ O)

 

Flying Scotsman

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CHANGE IT thats my vote on it. :^O it would not complyu to the 16th or 17th edition BECAUSE there is NO RCD to any socket outlets that could possibly be used outdoors

Dependant on main fuse the tails are not going to comply if the main fuse is 80-100 amps so they shold be in 25mm

and the main Earth to the met should be in 16mm not 6 :_| :eek:

There doesnt appear to be any 10mmequipotential bonding on the water and gas services as it is 6mm :_| :(

 
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Now I can't quote regs but I suppose it depends what the customer wants. If you fitted a stand alone RCD before the existing fusebox and swapped the wired fuses for MCB trips it would improve things.

You could also re-sheath the green cables green and yellow if you saw fit. The wiring is modern PVC and may well be ok. I don't think there's anything wrong with the cable sizes and this arrangement would suit many smaller houses. If customer wanted further circuits added then a new CU might be better idea. 46amps isn't a big load. No electric cooker or shower so ok. Do we have an immersion heater to think about?

Although this CU doesn't comply with the 17th IF you are not altering any circuits then I think the modifications I suggest above would improve the safety without requiring a complete CU change?

I must stress I'm an amature (with a signature now :D )

 
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CHANGE IT thats my vote on it. :^O it would not complyu to the 16th or 17th edition BECAUSE there is NO RCD to any socket outlets that could possibly be used outdoors Dependant on main fuse the tails are not going to comply if the main fuse is 80-100 amps so they shold be in 25mm

and the main Earth to the met should be in 16mm not 6 :_| :eek:

There doesnt appear to be any 10mmequipotential bonding on the water and gas services as it is 6mm :_| :(
How do you know that RCD sockets have not been fitted for that purpose.

How do you know that the main fuse is more than 60A and that if wired to a previous edition of the regs (or TT) then the main earth may be ok.

How do you know that the main bonding may be to a MET not visible in the pic.

 

emf

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:)Apache does seem on the ball. I cant wait till I know stuff like this!!!

 
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Fuse box should have bakelite board behind it. Must have got taken out at some point or maybe never fitted. Could have been second hand unit. Needs replacing as it doesn't have RCD protection.

batty

 

ElectekAir

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I would change it because the old light switches cannot be used ( the ones with the wooden back) the same goes for this one no wood can be used as part of an enclosure

 

dougal

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the 17th edition regs are not retrosective. as this is a P.I.R. rcd protection is not an issue. I belive the CU does need changing because of the fire risks, I would possibly use a code 1 for it due to fire risk

 
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Well...

lots of interesting comments so far....

I am not going to comment yet...

But.. if your customer disputes your judgement or observations can you back them up with any references??? ?:|

from post#1..

Try & justify with appropriate regs or guidance notes?
One of the NICEIC best practice guides does mention items are occasionally included in PIR as requiring remedial action...

BUT they are not actually departures from BS7671. :(

We have to keep it to actual departures from BS7671

NOT things that we would like to do cuz we think its common sense or good to do.. :|

And for those actually studying their C&G's getting a bit of extra familiarity with the regs often helps! ;)

 
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I was good - I went to bed. I behaved. I got up. Went to work. Waited ever-so patiently and yet no answer.

Apache not going to be back until sat and would like some answers!Pray

 
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