New FCU's.

[byronsmith]

Hi all,

Before I go and start tiling, and before I call a part P certified electrician to sign off my work. I would like to get your opinion please.

I have added 3 spurs in the kitchen off existing sockets.

1. I have a 30a cooker circuit with 6mm2 flex onto a cooker switch and socket combo (this already existed when I purchased the property) - I spurred off this switch with 6mm2 flex onto a 3a FCU. From that I ran a 2.5mm2 flex in the drywall which runs behind the wall cabinet and then across behind the oven hood chimney, to which the hood will connect.

2. I also spurred off a different 2.5mm2 socket onto a 13a FCU using the same 2.5mm flex, and from that ran a 1.5mm2 cable in the drywall up under the cabinet for lighting.

3. Exactly the same as number two but opposite wall.

All spurs are located next to the socket I spurred off off and are not in any zones.

Can anyone invisage any problems with this? Anything I need to remedy before I start tiling?

If all is good, I'll finish my tiling and get a sparky in to sign it off.

Thanks for your time.

 

[JohnW2]

Before I go and start tiling, and before I call a part P certified electrician to sign off my work. ... If all is good, I'll finish my tiling and get a sparky in to sign it off.

It doesn't work like that. You need to involve an electrician now. At the very least, (s)he would probably want to see the cables before you buried and tiled over them. If (as sounds to be the case) the spurs all originate from existing circuits, this will not be 'notifiable' work, but there still should be inspection, testing and certification.

The new buried cables creates a need for RCD protection. Are the circuits in question already protected by RCD(s)?

All spurs are located next to the socket I spurred off off and are not in any zones.

I'm not sure exactly what that means. All the new buried cables (in particular, those coming out of the new FCUs) need to be in 'safe zones' created by accessories - are you familiar with them?

Kind Regards, John

 

[byronsmith]

I have simply fished the cables in the 'safe zones' but upon further reading I think I'll need to bury then correctly.

Can you point me in the direction on the best method for bury cables into dry wall?

As for the RCD, yes, the circuit already has them.

The zones I was referring to was the wet zones. Apologies for the confusion.

 

[ericmark]

There is nothing to stop you filling in the Minor Works Certificate yourself you can down load the blanks from IET website FOC take the readings with your meters and fill in the form and sign it.

You can also get a three signature form and you sign for design and installation and some one else signs for inspection and testing. However to sign as inspected they must do that and with cables concealed in a wall that is a problem.

So if wires are threaded into a cavity then only the person doing that threading can sign for inspection. Where cables are in chases then another person can clearly see them before it is plastered.

There are so called safe zones and in a cavity we don't really know if the cable is in a safe zone. The Emma Shaw Case it seems all started where an electrician allowed a cable to loop and was damaged by the plaster then some plumbers also made some errors however the case hinged around who signed the inspection and testing and if he had the required skill and who asked him to do the inspection and testing. So the scape goat was the Foreman who had not even been on site.

Electricians are very aware of the problems in signing for work which others have done we know it's not permitted and clearly there are times when we don't follow the rules to letter but the Emma Shaw case was an eye opener for many of us and we are now far more careful about what we sign.

In the main HSE and other bodies will not take a owner occupier to court and the courts tend to not pile it on where errors have been made with DIY. But if a tradesman or a landlord make the same mistake then they go to town. So you make the call either DIY or don't DIY there is really no halfway. You can get an EICR which may highlight problems but that is not the same as an installation certificate or Minor Works certificate.

 

[JohnW2]

So you make the call either DIY or don't DIY there is really no halfway.

That used to be the case but it seems that at least some "Third Party Certifier" schemes are now up and running and that they have at least some members ("Registered Third Party Certifiers"). With that approach, however, it is necessary to involve the selected 'Certifier' before any work starts, and for the 'Certifier' to inspect work-in-progress at whatever stage(s) (s)he may see fit. Whether that is, in practice, likely to end up appreciably cheaper than getting a self-certifying electrician to actually do the work, I don't know!

Kind Regards, John

 

[byronsmith]

I don't think I'll risk the self signing!

I'll take your advice and leave the chase open for inspection

Attached are two images, one showing the safe zone chase for the cooker hood , and the other the opening where the 13a FCU will be spurred along with the lighting cable (fished up to the cabinet)

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• byronsmith
• 7 May 2015
• 1

Untitled

• byronsmith
• 7 May 2015
• 1

Thanks all for your help

 

[JohnW2]

I don't think I'll risk the self signing! ... I'll take your advice and leave the chase open for inspection

Fair enough - but, even if they can 'inspect and test', you may well still find that some electricians are uninclined to sign a declaration that they 'designed and constructed' the wiring when they didn't!

Attached are two images, one showing the safe zone chase for the cooker hood ...

Do I take it that the horizontal chase at the top is within 150mm of the ceiling? (it looks pretty marginal!). What is going to happen to the vertical run of cable down to the hood, and what is going to be on the end of it?

Kind Regards, John

 

[byronsmith]

It is within, 110mm to be precise. I have a feeling you're going to tell me to move it higher!

At the end will be a flex outlet plate for the cooker cable to connect, but I'm not 100% certain if it requires another fuse?. If I have a 3a fused dp switch near the cooker switch, that should be suffient right?

 

[JohnW2]

It is within, 110mm to be precise. I have a feeling you're going to tell me to move it higher!

Nope. If it's all within 150mm of the ceiling, that's reg-compliant.

At the end will be a flex outlet plate for the cooker cable to connect,

I'm a little confused. What do you mean by the 'cooker cable'? - are you referring to the cable to the hood? Provided the cable remains vertically aligned on the way down to that outlet plate, it will be within a safe zone'.

... but I'm not 100% certain if it requires another fuse?. If I have a 3a fused dp switch near the cooker switch, that should be suffient right?

Yep, no point in having two fuses in series.

Kind Regards, John

 

[byronsmith]

I'm a little confused. What do you mean by the 'cooker cable'? - are you referring to the cable to the hood? Provided the cable remains vertically aligned on the way down to that outlet plate, it will be within a safe zone'.

sorry, my bad. typing in a rush. I meant cooker hood cable, not the cooker!


The plate will be positioned behind the fake chimney and in line with the cable as it stands.

Thanks very much for your time and help. Much appreciated.

 

[JohnW2]

sorry, my bad. typing in a rush. I meant cooker hood cable, not the cooker! ...

Thanks for clarifying!

The plate will be positioned behind the fake chimney and in line with the cable as it stands.

Since the plate will contained screwed connections, it needs to be "accessible for maintenance, inspection and testing". Interpretation of "accessible" is open to debate, but would you feel that what you are describing could reasonably be regarded as "accessible"?

Thanks very much for your time and help. Much appreciated.

You're welcome.

Kind Regards, John

 

[deadshort]

6mm between the ccu and the fcu? odd ?


DS

 

[byronsmith]

That's what I thought. I was going to keep it 2.5 but someone suggested I maintain the flex size onto the spur. I guess is doesn't hurt to have larger. Safe as houses?

 

[JohnW2]

6mm between the ccu and the fcu? odd ?

Indeed. However, since the OP spoke of having installed it in the past tense, I (and perhaps others) didn't see any point in suggesting that he ripped it out and replaced with smaller cable. As he has said himself (and provided the cables fit in the accessory terminals, which I assume they did) it certainly does no harm.

Kind Regards, John

 

[Iggifer]

And later he can just replace the fcu with an oven! Future proofing! Hope he left a nice loop of cable.....