Type/size of wires? LED strip power supply (switched) + extraction fan

[john738]

Hi, I have to install an extraction fan and undercabinet LED strips in my kitchen. To feed these I want to run wires concelead in the plasterboard walls.

The LED strip power supply will be 36W and it will be connected directly to the CU.

I'm not sure what the wattage of the extraction fan will be as I haven't purchased one yet, but it will be just a regular kitchen extraction fan that I will likely spur off an existing socket, adding a fused switch for it.

What type and size of wire should I use for both? I was thinking of chasing the new wires in the plasterboard and using conduits to protect them.

Any suggestions would be appreciated.

 

[terryplumb]

The LED strip power supply will be 36W and it will be connected directly to the CU.

Your considering wiring the 36w LED directly Into the consumer unit ,what exactly are you connecting it to ?
If you are going to spur from a socket that is part of a ring final circuit 2.5mm² T&E for the spur.

 

[john738]

Your considering wiring the 36w LED directly Into the consumer unit ,what exactly are you connecting it to ?

Sorry I wrote that wrong, not directly connected to the consumer unit, there is an existing fused spur just outside the consumer unit where I'm planning to connect it

 

[john738]

If you are going to spur from a socket that is part of a ring final circuit 2.5mm² T&E for the spur.

Does it make sense to put the 2.5mm² T&E inside a conduit, or can I just run it as is?

 

[terryplumb]

The circuit should be protected by an RCD, the cables can run in the wall ( is it dot and dabbed plasterboard or a stud wall)?
The cables must be in safe zones ,essentially horizontal / vertical from accessories ,sockets/ switches/ fused connection units etc

 

[john738]

( is it dot and dabbed plasterboard or a stud wall)?

Thanks - It's stud wall

 

[ericmark]

2.5 mm² our unfused spur, 1.5 mm² for fused spur.

The question on RCD is seprate, I think whole house should be RCD protected, but using metal conduit or Ali-tube cable can get around the requirements.

 

[john738]

2.5 mm² our unfused spur, 1.5 mm² for fused spur.

The question on RCD is seprate, I think whole house should be RCD protected, but using metal conduit or Ali-tube cable can get around the requirements.

Thanks -

Yes the whole house is RCD protected - no need for conduit then?

 

[EFLImpudence]

Yes the whole house is RCD protected - no need for conduit then?

The two things are unrelated.

 

[john738]

The two things are unrelated.

OK, the "using metal conduit or Ali-tube cable can get around the requirements" part threw me off then.
I need to understand if using conduit is a must in order to comply with building regulations or if it's OK to chase twin and earth cable as is under plasterboard (stud wall) without any conduit. Can anyone chime in about this?

 

[EFLImpudence]

OK, the "using metal conduit or Ali-tube cable can get around the requirements" part threw me off then.

But you have RCDs so it does not apply.

I need to understand if using conduit is a must in order to comply with building regulations

It is not.

or if it's OK to chase twin and earth cable as is under plasterboard (stud wall) without any conduit.

It is.

I was thinking of chasing the new wires in the plasterboard and using conduits to protect them.

From what do you think the cable in plasterboard needs protecting?

 

[john738]

From what do you think the cable in plasterboard needs protecting?

Not sure to be honest, that's why I thougt better to ask. I'm not originally from the UK, and back in my country chased wires must be run inside corrugated conduit per building regulations. It's handy as this makes them accessible, i.e. they can be pulled out and replaced in the future, and I suppose they protect them from any possible chemical reactions once they are cemented or plastered over. Plasterboard, stud walls, etc are not common there, that's why I wasn't sure. Thanks so much for your help!

 

[EFLImpudence]

Not sure to be honest, that's why I thougt better to ask. I'm not originally from the UK, and back in my country chased wires must be run inside corrugated conduit per building regulations. It's handy as this makes them accessible, i.e. they can be pulled out and replaced in the future,

Fair enough.

They do that here. Not sure if it is compulsory or just because they use single wires instead of sheathed cable.
It is useful for the other reasons you state.

and I suppose they protect them from any possible chemical reactions once they are cemented or plastered over.

Mmmm maybe. Burying in cement (as long as sheathed) is perfectly acceptable in the UK and better for heat dissipation.
There is the flimsy 'oval conduit' used in the UK but it does nothing for protection.

Plasterboard, stud walls, etc are not common there, that's why I wasn't sure. Thanks so much for your help!