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[sparky12]

I have flourescent lights in my kitchen which have no earth wire, just red and black in and out, I want to replace with earthed down lights how do I earth

[ericmark]

You will note I have answered a similar question today already there is the link to Best Practice Guides.

I have in the past tried to find a florescent light unit that was double insulated and even the completely plastic type of corrosive environment were not Class II and it seems they are not available or at least they were not last time I looked so there should have been an earth.

1966 the rules changed for earths and since that time earths have needed to be provided for lighting and every 10 years or change of owner the electrics should be tested so any home owner should have been told at least 4 times a re-wire was required and will have had at least 34 years to find the cash so there are no excuses it should be re-wired and no "I didn't know" or "I have not got the money" excuse really can be used after 44 years.

So cure is re-wire and while waiting for it to start only Class II light fittings can be used.

As far as getting an earth from somewhere else it states the earth wire must run along the same route as the live supply and it will need to be at least 4mm sq if not part of the cable so the work in doing it correct is very little different to running an extra wire.

542.1.8, 543.1.1, 543.2.8, 521.8

[moggy1968]

if your lucky the lights are looped up in the ceiling void with just the live and neutral brought down. a bit of digging may reveal the earth. If it won't reach you can connect a length of earth cable to it to bring down to your light.
if not, your stuffed. you can't use a fitting that needs to be earthed without an earth

[raster ozi]

Regarding class 2 fleourescent fittings.

There is a way arround your problem. There are 2 sizes of fleourescent fittings available that just plug into a batten lampholder, 600mm and 900mm (2' and 3').

These do not require an earth connection and can be turned once plugged into the lampholder by upto 90 deg so they can be squared up to your room.

You should be able to find them in lighting showrooms and proper electrical stockists.

Hope that helps

[ericmark]

Years ago I remember the BA22d Fluorescent Light fitting but I have not seen them for quite some time. I would guess this is because of the Class II problem as I can't see how any fitting where metal is used to hold the tube could ever be class II. Even the Non Corrosive Weatherproof Fluorescent Light Fittings are not class II as when changing the tube you have to open the cover and there is a steel plate to which everything is fixed to that could under fault conditions become live.

The closest one can get is the energy saving bulb which has no earth connection.

Argos do sell fittings they claim "Plugs straight into existing lamp holder" and "No wiring necessary" but then say "All light fittings must be fitted in accordance with wiring regulations from the Institute of Electrical Engineers (IEE) and current building regulations. We recommend you employ a qualified electrician and that manufacturer's fitting instructions are followed."

So maybe there are some double insulated units but I would be very careful and be looking for the double square that shows they are double insulated. And they are all circular using 2D lamps not a long tube. And I checked the one 2D fitting I have and that does require an earth.

[Branta]

There ARE double-insulated fluorescent light fittings available.

They are called "slimline link lights" and are intended for use under kitchen cabinets to light worktops. The slimmest type (T4 tube) are all double-insulated (fed with a 2-core pluggable lead) which could be quite neatly fed out of a ceiling rose.

What's the problem with using these on the ceiling ? The T5 and T8 types are quite ugly and need hiding behind a pelmet (and need an earth, so forget it), but the "slimline" T4 type are pretty enough to have out on show, they even come with diffusers.

The only disadvantage I can think of is that the tubes have a shorter life than a regular T8 type.

[ericmark]

The 2D and T4 light fittings can be double insulated but in both cases 30W is about the maximum. My kitchen has 180W of florescent light with two fittings and to light with 2D or T4 would need quite an array of fittings.

However my mothers kitchen is more square and has good light from outside and under unit lights and a single 2D lamp is ample.

Since the guy has not re-posted any reply I would assume he has found a way around the problem? But when I had the same problem with my mothers kitchen it was finding a supplier local with double insulated lamps in stock that was the problem. In the end I had to send for a lamp and paid over the odds to ensure it was double insulated.

Although the T4 fitting may be double insulated if fact I am sure it is. The adverts don't list them as being double insulated and I was not prepared to take a chance. Some of the T5 linkable lamps also use the standard fig of 8 class 2 2.5A connection lead so must be double insulated. The problem is the rating of the connection lead as most houses use ceiling roses rated at 5/6 amp and have a 5A fuse or 6A MCB supplying the lights in the house. So to use the under unit lamps from the main lighting supply requires a fused connection unit to reduce to rating to 3A which as under unit lamps is not a problem but on the ceiling would be a problem and since each lamp has a socket and can be extended to another lamp it would require fusing down in case some one plugged into the lamp.

Also not sure on if they can be fixed. Because it has a socket outlet it needs a 5 second disconnection time and the regulations state.

412.1.2 The protective measure of double or reinforced insulation is applicable in all situations, unless limitations are given in the corresponding section of Part 7.
412.1.3 Where this protective measure is to be used as the sole protective measure (i.e. where a whole Installation or circuit is intended to consist entirely of equipment with double insulation or reinforced insulation), it shall be verified that the installation or circuit concerned will be under effective supervision in normal use so that no change is made that would impair the effectiveness of the protective measure. This protective measure shall not therefore be applied to any circuit that includes a socket-outlet, luminaire supporting coupler (LSC), device for connecting a luminaire (DCL) or cable coupler, or where a user may change items of equipment without authorization.

Also it states:-
418.3.5 Every socket-outlet shall be provided with a protective conductor contact which shall be connected to the equipotential bonding system provided in accordance with Regulation 418.3.4.

With view to this I would not want to sign off the job if these lamps with sockets were fitted as part of the fixed wiring. To my mind although OK as portable appliance I do not think these would be permitted as part of the fixed installation.

[Branta]

Thanks ericmark, some interesting points here, but to argue that they aren't suitable for part of a fixed installation is to argue that these are illegal in the application for which they are intended, because for sure they will be permanently wired-in if fitted under kitchen wall cabinets. Unless, that is, the fact that the only way of connecting them is via a pluggable lead is a deliberate getaround for this regulation, and qualifies them as "portable". Come to think of it, the way they use a plastic mounting clip instead of being screwed right to the cabinet might also be a gimmick to qualify them as "portable", but to me it is just very neat and convenient.

For sure the ones I have (from 2 different manufacturers) bear the double-insulated logo.

So my proposal is to use a ceiling rose (I guess that's a "luminaire supporting coupler (LSC)") which has no earth wire anywhere near it (this installation was legal in the 1960s and the changing regulations don't actually serve to make it "illegal" overnight), and have a pair of coupling flexes coming out of the rose. Then with 2 rows of 3 x 20W T4 lamps I have 120W of fluorescent lighting in the kitchen (about 600W in GLS terms), which in this kitchen I'm confident will be enough.

Right now he has 3 x 20W halogen spots (maybe equivalent to 80W GLS, but what a crazy idea to put spots in a kitchen) which are definitely NOT enough (and not double-insulated either !). I'll be leaving his house safer than it was before, I think my conscience won't struggle with this.