My hallway lights come on slowly or not at all

[Waggid]

Only started in the last day or so - but the up and downstairs hall lights are slow to brighten, sometimes not coming on at all. I've been into the garage a few times to check the MCB's on the consumer unit but they have not tripped. It looks like a single circuit is affected. I have powered the consumer unit down and back and this seems to stop the problem for a few goes.

Is this a symptom of the individual MCB on the way out or a symptom of a more serious problem?

For info: I have not changed any parts of the original household lighting circuit in the last twelve months.

 

[jj4091]

Do you mean low energy lamps or normal filament type?

 

[wingcoax]

It's highly unlikely to be the mcb as only one circuit involved(one light) more likely the bulb is on it's way out. Try fitting a new one.

 

[Waggid]

There are 3 rooms plus the hallway upstairs on the circuit, and the hallway downstairs as well as two external lights on the same MCB. The rooms upstairs are conventional filament type bulbs, the hallway upstairs uses 1 x low energy and one filament bulb [ 2 roses ]. The normal lamp lights up 'slowly' when having this problem, the low energy lamps dont light at all. The problem goes away once I cycle the power on the consumer unit, but returns after a couple of on/offs at the light switches. Its got me confused....

 

[ColJack]

it could be a loose conneection, or a misswired light?

you also don't mention whether there are dimmers on the circuit or not..

if there are dimmers than it may be faulty dimmer..

 

[ElectricDunc]

If there is a dimmer on the hallway it's most likely knackered anyway courtesy of the CFL on it. It does sound a bit like a loose connection but that would usually result in the light flickering or pulsing a lot.

 

[ColJack]

first thing to try is to swap out the bulbs...

 

[Waggid]

Thanks for the help folks -

There are no dimmer switches on the ring at all - just conventional on/off type.

I have now had all the switches off the walls and checked all for dodgy connections - none found.

I have now replaced the standard filament type lamps with new low energy type lamps.

I have also had more time to observe whats happening...

When all the lights in on the ring are switched off for some time and if any of the lights are then switched on they take some time to actually come on. BUT once one or more lamps in the circuit have been on for some time, the rest of the lights on the ring come on straight away..HOWEVER, there is a noticeable flicker when extra lights are switched on in the circuit...its almost as if the whole thing is taking time to warm up and then only just has enough juice to keep the lamps going...

I have checked the voltage drop from live on the MCB to the neutral rail on the consumer unit and its giving me 244v when the lights are all off rising to 262v when all the lights are switched on.

any ideas?

 

[rebuke]

The voltage from the live on the MCB to the neutral rail shouldn't change just because there is added load, something is very wrong there if that's happening.

I don't know enough about this to be sure, but could it be something like a PME system where the incoming neutral has been lost, so the MEB is being used as a neutral, hence there's effectively a high resistance joint, which as things heat up gets better?

If it is something like I've suggested, that is a very bad scenario, and should be rectified ASAP. Certainly if you're readings are as you suggest, I'd get an electrician in with proper test gear who can hopefully figure out what's going on and sort it out - it could be very dangerous at the moment...

 

[ElectricDunc]

Something very wrong there, i had a similar thing happen when the main neutral at a hotel was left disconnected on the main supply. Somehow it had found a neutral through somewhere else but as it broke down the voltage started to spike. This was on a 3 phase system mind, do you have a 3 phase supply by any chance. Have you noticed any problems anywhere else in the house? The problem may be external to the property if the fluctuations in voltage are at the intake. May indicate an issue at the transformer which would be very bad news.

 

[electronicsuk]

In any case, it sounds as if you need to get an electrician in to look at the problem ASAP. If you have changed any fittings recently then you could have ended up with some sort of odd series-parallel combination of wiring, which allows more current to pass through the incorrectly wired lamp as more lighting on the rest of the circuit is switched on. If nothing has changed then this seems unlikely, and it also doesn't fit with the voltage readings you describe.

 

[RF Lighting]

I have checked the voltage drop from live on the MCB to the neutral rail on the consumer unit and its giving me 244v when the lights are all off rising to 262v when all the lights are switched on.

Could you possibly re-do this test, but this time test between the same live as before but instead of the neutral bar, to the earth bar this time, and then also take a couple of readings between the neutral and earth bars?

It does sound that something could be very wrong there though.

Keep us informed, we like obscure faults

 

[Waggid]

Thanks for all the assistance folks - it has been really appreciated.

I've decided I'm out of my depth a bit, and a real electrician is coming to have a look.

cheers

 

[RF Lighting]

Just seen your post. Don't feel you have to do the above tests if you do not feel comfortable doing so.

I would hate for you to get injured just because of my curiosity.

Please keep us informed though

 

[ban-all-sheds]

Please keep us informed though

I second that.