23 lamps in a month BLOWN! carrier bags full of lamps blown over the past six months

[ianbrookes]

I have been asked to look at a problem for a customer.

they have had 23 lamps blow in the last month - they haven't replaced them as they say some blow almost immediately.

I plan to do a visual inspection of the lamps holders, wiring, switches etc and then some testing on the circuits and supply.

It looks like the house has been extended several years ago and the new lights (GU10's) are not blowing.

has anyone ever seen anything on this scale before ? apart from crappy lamps, loose connections, bad lamps holders etc what should I be testing for.

I had a quick look at the supply and I was a bit confused as it looks like PME, but there is also an earth stake(s) outside connected to an earth bar along with the PME.

THX.

 

[telectrix]

Re: 23 lamps in a month BLOWN! carrier bags full of lamps blown over the past six mo

think you've covered it. let us know what you find. voltage spikes on supply might be the answer.

 

[needasparks]

Re: 23 lamps in a month BLOWN! carrier bags full of lamps blown over the past six mo

Didn't someone on here mention the use of dimmers on gu10's limit the life or such, something about lamp not getting to temp and self cleaning. but my money is on tesco's own brand lamps lol

 

[alarm man]

Re: 23 lamps in a month BLOWN! carrier bags full of lamps blown over the past six mo

could be a poltergeist...

 

[Marvo]

Re: 23 lamps in a month BLOWN! carrier bags full of lamps blown over the past six mo

If it's only happening on one circuit then my money would be on a bad connection somewhere.

 

[needasparks]

Re: 23 lamps in a month BLOWN! carrier bags full of lamps blown over the past six mo

Thinking about Marvo's comment is Checking the lamps really have blown an idea.

 

[swparksey]

Re: 23 lamps in a month BLOWN! carrier bags full of lamps blown over the past six mo

Wow that is a lot of lamps, don't forget to let us know what you find
I had a problem with a extension blowing GU10's once, turned out to be a heat problem, with the builder installing the electrics, and covering them in thermal. They would just go after a week or so

 

[Knobhead]

Re: 23 lamps in a month BLOWN! carrier bags full of lamps blown over the past six mo

my money is on tesco's own brand lamps lol

Cheapskate customer's, all ways a good suspect!

 

[MarkieSparkie]

Re: 23 lamps in a month BLOWN! carrier bags full of lamps blown over the past six mo

The main suspects are:
1) Poor quality lamps.
2) Over-voltage, +5% over-voltage will more than halve the life expectancy of the lamp.
3) Loose connections.
4) Poor quality lamp holders, particularly batten fittings.
5) Power quality, surges, noise and harmonics can all shorten the life expectancy of the lamp.

 

[aiden251181]

Re: 23 lamps in a month BLOWN! carrier bags full of lamps blown over the past six mo

ive had same problem where i work, gu10's blowing constantly, they were installed by a contractor and were on dimmers, there were 2 loose connections i found this didnt solve the problem although they lasted slightly longer afterwards, so took the dimmers out, also didnt solve the problem so i replaced the lamps with LED lamps and hey presto they've not blown since.

 

[Inteificio]

Re: 23 lamps in a month BLOWN! carrier bags full of lamps blown over the past six mo

LEDs are the way forward!

 

[Rockingit]

Re: 23 lamps in a month BLOWN! carrier bags full of lamps blown over the past six mo

The main suspects are:
1) Poor quality lamps.
2) Over-voltage, +5% over-voltage will more than halve the life expectancy of the lamp.
3) Loose connections.
4) Poor quality lamp holders, particularly batten fittings.
5) Power quality, surges, noise and harmonics can all shorten the life expectancy of the lamp.

You missed out vibration! One floors floor is another floors ceiling - I know this from personal experience due to living with a herd of elephants - sorry, I mean teenagers. I could always tell if there'd been a mother-daughter disagreement as half the downstairs lights were out when I got back. No longer, as have replaced them for LED. The lamps, that is. I'd love to replace the daughter as well, but you can't have it all.

 

[Engineer54]

Re: 23 lamps in a month BLOWN! carrier bags full of lamps blown over the past six mo

I had a quick look at the supply and I was a bit confused as it looks like PME, but there is also an earth stake(s) outside connected to an earth bar along with the PME.

No problem at all with having an earth rod connected to the MET of a PME installation. Probably a PME converted TT system!! Don't worry about it and leave as is...

It won't be the cause of your lamp blowing problem, which others have covered to just about the tenth degree!! lol!!

 

[ianbrookes]

Re: 23 lamps in a month BLOWN! carrier bags full of lamps blown over the past six mo

Here is what I found: Not sure about the reversed wiring issue.

1. Downlights in the dining area of kitchen. When the lights were fitted the earth cable was cut short at not sheathed. In one light fitting the earth wire had worn through the live wire and was almost welded to it. The light fittings had corroded terminals.
2. Downlights in the small living room. The wiring behind the switch was loose. The live wire was not connected. Three of the downlights were wired in reverse, i.e. Neutral to Live and Live to Neutral.
3. Downlights in the kitchen. Badly terminated wiring behind all the downlights. Behind one of the downlights near the cooker is a mass of wires, some of the sheathing had be eaten by rodents. The wiring was also badly terminated.
4. Two way switching in the hall/landing. Loose wires behind the switches.
5. Living room lights. A double dimmer was wired from different circuits with only one neutral behind the switch and some kind of DIY strapping of the commons!
6. Downlights in the small living room. The wiring behind the switch was loose. The live wire was not connected. Three of the downlights were wired in reverse, i.e. Neutral to Live and Live to Neutral.
7. Two way switching in the hall/landing. Loose wires behind the switches.
8. Fuses in fuse board had cartridge style fuse holders. The cartridges had been removed and 15amp fuse wire wrapped around the terminals.

 

[Fin170]

Re: 23 lamps in a month BLOWN! carrier bags full of lamps blown over the past six mo

So now you'll do it as they B&Q'd it?