Quote

[avinalarf]

Just been to look at a job...

A variety of switches need moving, due to doors having been moved, segregating light circuits and adding a new switch for utility area.

TNC-S installation. The CU was an old MEM with an external 63A Newlec main switch. There was NO RCD protection . Earthing was 16mm and tails were 25mm.

Anyway, apart from moving switches, I may need to upgrade the supply to the shed as it's been done in T&E :_| and the client said that when they attempted to switch on the pond pump, everything went off

They will also need a new circuit to provide for an electric cooker.

Personally, I feel that they should have a new CU. I just wanted to know at what stage this would be deemed "absolutely necessary" - if at all.

Thanks

N

 

[Theorysparky]

Ask yourself this

cooker cct is there a spare way ? and it needs needs rcd/rcbo

new light switch requires rcd/rcbo

outside work (if you do it) requires rcd/rcbo

so thats 3 lots required already

i would recommend a new CU on this alone

 

[ianmacd]

Well you will need RCD on any lighting circuits with wires not protected in walls >50mm so may as well get a new 17th board. Is the shed TT'd too as you can't export earth's on PME?

Ian.

 

[ianmacd]

cooker cct is there a spare way ? and it needs needs rcd/rcbo

If the cooker switch doesnt have a "general use" socket on it and the wires are not run in walls >50mm etc...... then you do not need an RCD on a cooker circuit. That does not mean you shouldn't have one though .

Ian.

 

[avinalarf]

Thanks Guys

With this in mind - is there any point me doing any of the work before they agree to a new CU? I ask because they want me to break down all aspects of the work and give a price for each :_| .

Is it worth pricing to move the light switches or do they instantly need rcd protection due to them being moved?

They want to get the switches moved rather soon due to pending decorative work!

 

[ianmacd]

You will need rcd protection when you move them if the cables are in walls under 50mm, etc.......

Ian.

 

[Theorysparky]

If the cooker switch doesnt have a "general use" socket on it and the wires are not run in walls >50mm etc...... then you do not need an RCD on a cooker circuit. That does not mean you shouldn't have one though .Ian.

Ian

i make the assumption on all my replies that it will be buried at some stage in the wall less than 50mm

 

[Theorysparky]

Well you will need RCD on any lighting circuits with wires not protected in walls >50mm so may as well get a new 17th board. Is the shed TT'd too as you can't export earth's on PME?Ian.

yes you can in certain situations

 

[ianmacd]

yes you can in certain situations

You care to expand on that?

 

[avinalarf]

I think I'll worry about the outside supply and TTing/not exporting earths etc later on!

 

[Theorysparky]

Thanks GuysWith this in mind - is there any point me doing any of the work before they agree to a new CU? I ask because they want me to break down all aspects of the work and give a price for each :_| .

Is it worth pricing to move the light switches or do they instantly need rcd protection due to them being moved?

They want to get the switches moved rather soon due to pending decorative work!

rcbo the light cct as long as its not a rewireable board

otherwise standalone rcd

quote for each bit of the work but make sure that at each stage your work complies with the regs just in case they decide they dont want and further work doing

so you could end up withe 3 seperate rcbo ccts before you replace CU

 

[avinalarf]

Client is willing to chase out etc, but I'll have to lift carpets, cut floorboards, locate original switch cable and then relocate. Is

 

[Theorysparky]

Client is willing to chase out etc, but I'll have to lift carpets, cut floorboards, locate original switch cable and then relocate. Is

 

[avinalarf]

minumum + materialsdont forget the rcd and testing of cct

Theory, the CU looks pretty old! It's not re-wireable, but I'm not sure if it'll take RCBOs Blushing.

Regards testing...if someone just pulled up the old switch cable and used the same cable to relocate the switch without breaking into the circuit or anything, would testing still be required???

Also, aren't external RCDs more money? It wouldn't have to be the same make as the CU would it?

 

[ianmacd]

you are still modifying the cable run of the circuit so it would still need testing and an RCD. These are both for safety and should not be "worked around".

An external RCD will cost more yes, hence the recommendation of a new CCU.

Ian.

 

[avinalarf]

you are still modifying the cable run of the circuit so it would still need testing and an RCD. These are both for safety and should not be "worked around".

I asked that so I could deter the client from attempting to do it himself, in case my quote was too high!

 

[Apache]

Regards testing...if someone just pulled up the old switch cable and used the same cable to relocate the switch without breaking into the circuit or anything, would testing still be required????

This is what seperates you from the cowboys cowgirls!

Also, aren't external RCDs more money? It wouldn't have to be the same make as the CU would it?

Such a minor change Deke will come on later and say just do it

 

[Theorysparky]

you are still modifying the cable run of the circuit so it would still need testing and an RCD. These are both for safety and should not be "worked around".An external RCD will cost more yes, hence the recommendation of a new CCU.

Ian.

i agree

 

[avinalarf]

This is what seperates you from the cowboys cowgirls!

Absolutely! ("separates" BTW) Wouldn't dream of doing anything without necessary testing

 

[Apache]

Absolutely! ("separates" BTW) Wouldn't dream of doing anything without necessary testing

I have a spell checker @ home