what is considered as design for re-wire

[unclebob1]

Good Afternoon all,

I'm looking to employ a registered electrician to rewire my property, however i want some specific setups:
1) each of the lights downstairs i want wired in 2 way (or more) to a relay in a central location,
2) I want spur's available under the stairs for future 12v lighting project
3) I want spur's available in the floor space between the ground and first floor - again for a future 12v lighting project.

I'm assuming this is actually classed as specification rather then design - at least for 2 and 3. But what about the first one? is that classed as specification or design? and ( i understand it will be the elec's discretion) the relay unit that i want at the end of it - so long as it meets bs standard would that be sufficient?

The idea of the relay unit is to allow control from rasperrypi/computer etc at a later date but if i can get the 240v side setup now, no need for any alterations to that side later.

 

[Aragorn84]

1 is a specification, and its not really at the electricians discretion, he just has to design what you want in a safe manner.

There was discussion recently about using ELV switching for all lighting in a property, that might be an option here?

 

[JohnW2]

1) each of the lights downstairs i want wired in 2 way (or more) to a relay in a central location,
2) I want spur's available under the stairs for future 12v lighting project
3) I want spur's available in the floor space between the ground and first floor - again for a future 12v lighting project.
I'm assuming this is actually classed as specification rather then design - at least for 2 and 3. But what about the first one? is that classed as specification or design?

I would say that all three are specifications, it being up to the designer (electrician) to design so as to implement that specification (provided that (s)he feels that there is an acceptable way of achieving that). That does not preclude your making suggestions/requests about design (e.g. the preferred nature of the relays) for the designer to consider.

One potential issue with (3), and possibly also (2), is that you are not allowed to have 'joints' (which includes connections to junction boxes and accessories) which are not 'accessible' for maintenance, inspection and testing - the one exception being 'maintenance-free' junction boxes.

Kind Regards, John

 

[unclebob1]

1 is a specification, and its not really at the electricians discretion, he just has to design what you want in a safe manner.

There was discussion recently about using ELV switching for all lighting in a property, that might be an option here?

I ment in terms of what goes on the end of it - the relay wouldnt be something that you can pick up off the shelf at screwfix for example.

and for ELV - I replied to the designer/implementer of that solution, however the level of bespoke hardware was not feasable for me...

I've opted for a set of relays http://www.switchtec.co.uk/downloads/brochures/Switchtec_SCLR2_Data_Sheet.pdf which will handle 12v - 240v side, and then a 12v relay board to sit between pi/computer and the sclr2 handling 5v-12v side...

As far as the electrician's work would be is to install the wiring upto and including the SCLR2 relays... I can handle the 12v side from there. The relays are 16A and "CE marked" whatever that means in today's world of copycats so hoping the electrician wont have an issue... worse case I'll have to get a box of 2 way singles switches and let him wire up to them, and then replace with the relays once signed off.

 

[unclebob1]

One potential issue with (3), and possibly also (2), is that you are not allowed to have 'joints' (which includes connections to junction boxes and accessories) which are not 'accessible' for maintenance, inspection and testing - the one exception being 'maintenance-free' junction boxes.

Kind Regards, John

Thanks John,
The joints will eventually be pulled though the corners of the rooms to connect transformer for LED strip light, at which point the wiring will come out. If in the meantime the elec wont sign off then i guess it will be a mf junction box connecting to nothing until I'm ready, then punch a hole in the ceiling or lift up boards to disconnect the junction box and push down the ceiling.

 

[JohnW2]

Thanks John, The joints will eventually be pulled though the corners of the rooms to connect transformer for LED strip light, at which point the wiring will come out. If in the meantime the elec wont sign off then i guess it will be a mf junction box connecting to nothing until I'm ready, then punch a hole in the ceiling or lift up boards to disconnect the junction box and push down the ceiling.

Yes, if the electrician wants to play things strictly by the book (and depending upon their interpretation of the regs), then (as I was implying) (s)he might possibly think that is necessary to do that (although it's a bit daft to be concerned about whether a 'joint to nothing' is accessible! - indeed, I think one can easily argue that it is not a 'joint').

Kind Regards, John