Will this pass an inspection by the building inspector?

[skellem]

I've just rewired my living room lights, and seeing as I don't have any formal training in wiring (although I think I'm pretty competant) I'd just like some input from you guys so that when I call the inspector in he doesn't laugh at me and tell me to rip it all out )

The general idea is 4 lighting circuits running a maximum of 7 50W halogen downlights per circuit. (I think one is 7, second one is 6, third is 6 and fourth is 4) I've followed the advice of a B&Q guru who seemed pretty clued up and used a central heating box. I took the mains from the existing ceiling light and wired up 4 separate cables to the switches. I then took another cable to the individual circuits. All this is using 1.5mm cable. Here's a snap of the box (sorry about the slightly large image - I wanted it to be nice and clear!!) :

 

[skellem]

I forgot to add that all the metal backboxes in the wall for the switches have been earthed from the existing earth as well.

Oh, how do I work out what rating I need for a dimmer switch to power 7 X 50W halogens? I have forgotten the formula

 

[breezer]

sorry, it fails.

no earth sleaving on exposed earth wires
no red tape / sleaving on switch wires
radius too tight on interconnections
its got "blue writing disease"
and to be really picky, cables are stripped to different lengths

formula for dimmer switch calculation with halogen lights

total power (w) x2= answer

eg

7 lamps @ 50w each = 7 x 50 = 350 watts

350 x 2 =700

so you want a 700w or higher rated dimmer

this is because most dimmers should be down rated by 50% if dimming halogen lamps

 

[skellem]

radius too tight on interconnections

When I bought the box it came with interconnectors that had exactly the same radius (ie connecting from one block directly to its neighbour)

The rest of the things I'll sort out asap, thanks for the help!

 

[Paul_C]

so that when I call the inspector in he doesn't laugh at me

The new part P requirements don't come into effect until January, so why
would you want to call the building inspector anyway?

Even if you did call him, he has no authority to tell you to do anything with your wiring -- Yet!

 

[JerryD]

Is it my eyesight or are there only 3 earth wires for the 7 cables?

 

[ban-all-sheds]

No - not your eyesight - looks like our supplicant has cut them back. Presumably the luminaires are Class II, but he's now made it impossible for anybody to fit Class I items, and has cables with no functioning cpc.

Another failure - lot of ripping out to do.

Whilst on the subject of cpcs, I note that connector positions marked on the box as being Earth, are not being used for that - is that a concern?

And whilst on the subject of the box, it looks to me as though the cores at the top of the photo are going to get trapped by the cover.


Just think how much neater it would have been to use a small box with a DIN rail and some terminals interconnected with bus-bars....

 

[kendor]

One obvious mistake is that there are only 3 lighting circuits connected in the box not 4

 

[skellem]

Paul, I just wanted to play it safe. I wanted to either get a sparky to check what I have done or the inspector. I'd rather be safe than sorry!

Jerry, I have only run an earth to the light switches, the downlighters don't need an earth.

Ban-all-sheds, as the box is from a central heating system, I could't use it as it was intended. Also, the cover doesn't trap the wires, there's enough space!

Kendor, the 4th circuit is the one that says "spare" while I decide how to wire them all up!

 

[Newspark]

What is the black wire going to the 3rd earth terminal?

 

[breezer]

Jerry, I have only run an earth to the light switches, the downlighters don't need an earth.

sorry that doesnt matter, you still have to run the earth, (put the end in choc bloc) the reason, what happens when you change the lights?

 

[plugwash]

leaving earth wires unconnected is a very bad thing for two reasons

the first issue is that it reduces the chance of a protective device tripping if something penatrates the cable.

the second issue is if people see an earth core they will often assume that it is actually connected to earth

 

[Paul_C]

Paul, I just wanted to play it safe. I wanted to either get a sparky to check what I have done or the inspector. I'd rather be safe than sorry!

Fair enough, and a commendable approach. I'd go with a sparky though. I doubt that a local building inspector would be (a) interested and/or (b) have any idea whether it was safe or not.

I'll echo the question about the black wire connected to the earths. It looks as though it might just connect to the earth coming in through the back of the box via that single choc-block. Shouldn't really use black for this, if so.

 

[ban-all-sheds]

I doubt that a local building inspector would be (a) interested and/or (b) have any idea whether it was safe or not.

[cynic]You're quite right, and for those reasons he'll sub it to a local spark, probably NICEIC, who will be hell bent on finding problems just to prove that DIYers should not do electrical work...[/cynic]

 

[skellem]

Ok, thanks for the comments guys.

The black wire BTW is the earth from the existing wiring. I didn't have any cable the right colour so I used black!

I'll do a little remedial work this weekend. I'll connect the earth on all the wires going to the lights and put some earth sleeving over the bare wires in the junction box. I can already feel my arms aching from working overhead for another couple of hours

Edit: I'll put some red tape on the switch wires as well