lights in bathroom mysterioulsy fail to work

[ban-all-sheds]

But it doesn't, hence why checking the switch should be the first step. The OP could have done that in less time than he's spent so far typing stuff here....

 

[boilerfrustration]

The bulbs are standard GU10 so I would think that the voltage is 240. I don't recall the electricians installing a transformer per fitting.

 

[PrenticeBoyofDerry]

Have you checked whether the swicth is faulty yet?
If you have a multi-meter, you can test for both supply voltage and whether the switch is operating correctly (ie opening and closing the switch contacts) by testing for voltage between com/L and earth and neutral (if present at the switch), then the same with L1/L2 (dependant on how installed) and earth and neutral.

NB: do not forget that the blue core on switch lines of twin and earth can be used as a line conductor, so may not be a neutral.
It could also be possible that the fan switch line and com/perm L are supplied via he switch rather than looped at the light fittings.
So they maybe things other things to consider. A loose connection at the supply, feed or load side of either line or neutral could contribute to complete power loss.

 

[boilerfrustration]

I will check to see if the switch is faulty. I'm not at home just yet but will be able to have a look this evening.

 

[boilerfrustration]

You were right. The switch was faulty. The switch is a double dimmer. One of the modules had packed in. The electrician also discovered that the lighting throughout the property was on one circuit. He said the regulations require that there be at least 2 circuits for health and safety reasons to avoid total black out. Am I within my rights to go back to the electrician who wired up the flat from scratch a few years back to put right?

 

[JohnW2]

The electrician also discovered that the lighting throughout the property was on one circuit. He said the regulations require that there be at least 2 circuits for health and safety reasons to avoid total black out. Am I within my rights to go back to the electrician who wired up the flat from scratch a few years back to put right?

Although such is how many people interpret them, the regulations do not explicitly require multiple lighting circuits - there is just a rather vague requirement (since 2008, I think) that the installation be separated in circuits so as to 'minimise inconvenience' in the event of a single fault. There is obviously a fair degree of scope for debate as to what satisfies that regulation. Even if (as commonly) one has separate 'upstairs' and 'downstairs' lighting circuits, other than for landing/hall lights, the availability of light on one floor won't really help much in rooms on the other floor.

Kind Regards, John

 

[boilerfrustration]

As this is a flat with no other levels, I wonder if the requirement for more than one circuit is more important.

 

[JohnW2]

As this is a flat with no other levels, I wonder if the requirement for more than one circuit is more important.

Well, splitting the lighting into more than one circuit would probably be more useful in a flat, since light in some rooms would probably mean that (with doors open) none would have to be in total darkness.

Having said that, I'm not sure what the common practice is in flats, particularly small ones. If, for example, there with just 3 or 4 rooms, each with just one light, one might wonder whether that really justified two lighting circuits! If there are lights (table lamps, standard lamps etc.) which operate from a sockets circuit, then (particularly in a flat) loss of a lighting circuit (or loss of 'all lighting circuits') is obviously less of an issue/concern.

Kind Regards, John

 

[PrenticeBoyofDerry]

The electrician also discovered that the lighting throughout the property was on one circuit. He said the regulations require that there be at least 2 circuits for health and safety reasons to avoid total black out

No such requirement/regulation exists

Am I within my rights to go back to the electrician who wired up the flat from scratch a few years back to put right?

Based on that it is not a regulation, No.

 

[EFLImpudence]

Am I within my rights to go back to the electrician who wired up the flat from scratch a few years back to put right?

No. Go back to this electrician and tell him to read his book and get some common sense.

I suppose to do it he would have to replace the consumer unit as well.

 

[endecotp]

In my building, smaller flats (1/2 bed) tend to have single circuits and larger flats (2/3 bed) tend to have two circuits.

 

[JohnW2]

In my building, smaller flats (1/2 bed) tend to have single circuits and larger flats (2/3 bed) tend to have two circuits.

That makes sense. Two lighting circuits for a 1-bed flat would seem a bit OTT!

Kind Regards, John

 

[PrenticeBoyofDerry]

I have rewired 1 and 2 bed bungalows making two light circuits and two socket circuits: L/R hand of property Lights/Sockets and L/R hand Sockets/Lights

 

[securespark]

No such requirement/regulation exists

Yes there is. Even in the 14th Ed (1966) there was mention of this:

A25. Note 2. In the interests of good planning, it is undesirable that the whole of the fixed lighting of an installation should be supplied from one final sub-circuit.

Then in subsequent 15th (314-1), 16th (314-01-01) & 17th Eds (314.1), something like: Every installation shall be divided into circuits as necessary to avoid danger in the event of a fault.

 

[JohnW2]

Then in subsequent 15th 16th & 17th Eds, something like: Every installation shall be divided into circuits as necessary to avoid danger in the event of a fault.

Indeed. The current version of 17th says "Every installation shall be divided into circuits, as necessary, to ... (i) avoid danger and minimize inconvenience in the event of a fault" .... (iii) take account of hazards that may arise from the failure of a circuit such as a lighting circuit...". However, that is all pretty vague and is open to a wide range of opinions/interpretations ... one man's "inconvenience" is another man's excuse to take his partner to bed early

If, as many seem to believe, one of the primary intents of the regulation is to prevent people being 'plunged into darkness' (maybe whilst up a latter, holding a pan of hot oil or whatever), then requiring 'division into circuits' would simply not be enough - they would have to insist on emergency lighting.

Kind Regards, John