Led downlighting bulb failing?

[Sealo0]

Hi all

 

just wondered if someone could help?

 

I have a bank of five led downlights , controlled by dimmer ( Varilight).  I had these fitted approx 10 years ago, we have replaced most bulbs in that time.
 

The last bulb in line keeps blowing, in fact it just gets dimmer then goes out. I must have changed six / seven bulbs in under two years. I brought some good quality replacements( I thought ) but it still keeps happening. 
 

Could it be the fitting or the dimmer or the wiring , which would be the worst one to fix? 
 

Any help would be appreciated.

 

regards

 

Mike

[Nickfromwales]

What voltage and wattage are the bulbs please? 
 

PS, calling them bulbs really pee’s off the electricians, so I’ll give you £1 every time you do it  

 

“You plant bulbs”……. Yea yea, get over it lol. 😜 

 

I expect the wiring is too small, can you get a second cable to loop from the last (lamp) to the 1st one? This will create a ring and even out the power each…….bulb…….receives. 
 

Probably an under-volt issue caused by the drop over the length of the cable, imo. 

[Sealo0]

Hi Nick.

 

thanks for the reply. 
 

All bulbs! Are 7 watt @ 240 volts. As I said before it was fitted about 10 years ago by a qualified electrician, not me. I think it was 2.5 mm cable some 5 meters from the switch with another 7/8 meters back to the RCD. Something I didn’t say before was this lamp did not go straight out when they were switched off, it slowly dimmed down, odd. 
 

To add a loop would be a challenge to say the least. Is there any testing I could do to understand what is going on? 
 

hope that’s all the questions answered. 
 

again thanks for your help. 
 

Mike

[SteamyTea]

13 hours ago, Sealo0 said:

The last bulb in line keeps blowing

Is it getting hotter than the others, maybe a ventilation/airflow problem.

[markc]

Is the dimmer suitable for LED’s ? Assuming yes then you are looking at a faulty fitting (if just replacing the lamps but keeping the same fitting), heat or humidity are also factors for premature failure especially with dimmed lighting.

[Nickfromwales]

8 hours ago, Sealo0 said:

Hi Nick.

 

thanks for the reply. 
 

All bulbs! Are 7 watt @ 240 volts. As I said before it was fitted about 10 years ago by a qualified electrician, not me. I think it was 2.5 mm cable some 5 meters from the switch with another 7/8 meters back to the RCD. Something I didn’t say before was this lamp did not go straight out when they were switched off, it slowly dimmed down, odd. 
 

To add a loop would be a challenge to say the least. Is there any testing I could do to understand what is going on? 
 

hope that’s all the questions answered. 
 

again thanks for your help. 
 

Mike

Cheers. 2.5 would be huge, prob 1.0 or 1.5?

 

OK, my fears of them being 12v is now quashed, so the extra cable run may out of the window (for dealing with the voltage drop) but……
 

Next thing is, I have a pair of LEDs in my living room, wall wash, and these also the same thing; the second one is slowest to come on but is always the first lamp to blow. I have a Varilight dimmer (from TLC Direct iirc) and the dimmer AND lamps are both ‘dimmable’. 
 

If I put a switch on in place of the dimmer, problem goes away. Can you try this please? Turn off the power, put both wires in the switch into a connector block, then have someone else put the power back on / off and report the results plz.

 

Mine don’t ‘blow’ as quickly as yours do but you’ve got a longer circuit. 

[Marvin]

Interesting.

 

We have multiple GU10 brands, some different wattages with different brightness and angles.  

 

Some get hotter than others and I think this is a factor. Also I seem to remember reading that ceramic domed ones are better in regard to heat problems. We have about 50 installed. Some have so far lasted 8 years with high use.

 

WE mainly use GU10 4W 120 degree warm, cool, or daylight.

 

 

@NickfromwalesDid you see how I managed not to mention Bulbs? 🤬 I just mentioned them.

 

 

 

 

[JohnMo]

In our last house we had GU10 led things (if not bulb, what do you call them?). They had a poor installed life, tried a few differences they were all rubbish.

 

Think the main issue, the GU10 holder isn't optimised for the cooling LEDs need, so they overheat and fail quickly, dimmers and 7W don't help either.

[Nickfromwales]

Just now, JohnMo said:

if not bulb, what do you call them?

Ask the regimental electricians and you’ll get told……..”LAMPS!” lol.  
 

 

[JohnMo]

4 minutes ago, Nickfromwales said:

Ask the regimental electricians and you’ll get told……..”LAMPS!” lol.  
 

 

Back to the good old days of oil lamps then

[G and J]

Hang on.  
 

Has someone worked out how much more in resource terms these so called eco but actually short lived led bulbs (that’s what John Lewis calls them so I’m sticking to that) cost vs dead simple and resource friendly filament bulbs cost?

 

I know filaments use more lecky but is it enough to justify all the plastic and precious metals that get thrown away?

[JohnMo]

4 minutes ago, G and J said:

know filaments use more lecky but is it enough to justify all the plastic and precious metals that get thrown away?

Come on now, you can't simply tick a box that says "eco" if you need to do some justification. That just isn't a easy to do.

[Marvin]

3 minutes ago, G and J said:

Hang on.  
 

Has someone worked out how much more in resource terms these so called eco but actually short lived led bulbs (that’s what John Lewis calls them so I’m sticking to that) cost vs dead simple and resource friendly filament bulbs cost?

 

I know filaments use more lecky but is it enough to justify all the plastic and precious metals that get thrown away?

Hi @G and J This is a fluid question.

 

The GU10s have gone up and down in price. The range of choices is now so big as to require a spread sheet to list them. Different makers produce different qualities with different designs with different materials.

Different installations with different temperature extremes, being turned on and off more or less frequently. The list goes on and on.  

 

You can buy them for 79 pence each now. The first ones I bought cost 3.75 each. You can also pay £7.99 for 1 thingy. 

 

I have clients who have had the same GU10's for over 20 years without replacing one (these were all glass domed ones).

 

I had one client where the same bulbs kept blowing. I put it down to the poorly built cold flat roof allowing a breeze to blow through...

 

[markc]

As an apprentice sparky in a steelworks we were told a Bulb if it has a simple filament, Lamp if it is an assembly or has an igniter built into the “Bulb”.

[ProDave]

A "Bulb" is something you plant in earth and it grows into a plant.

[Nickfromwales]

2 minutes ago, ProDave said:

A "Bulb" is something you plant in earth and it grows into a plant.

I knew if I left the worm on the hook long enough I’d get a bite lol. 

[Post and beam]

A bit like the screws & bolts question.

 

Sorry to hijack but this is fun.....

[markc]

3 minutes ago, Post and beam said:

A bit like the screws & bolts question.

 

Sorry to hijack but this is fun.....

Naarrr, that’s easy … they are all helical retaining units

[SteamyTea]

7 hours ago, JohnMo said:

if not bulb, what do you call them

Elements?

 

Luminaire is the correct term for the complete light fitting.

[SteamyTea]

4 hours ago, Post and beam said:

bit like the screws & bolts question

No, that is clear cut and easy to understand.

Just a shame that many people refuse to accept the difference and argue that it is the tools used to fit them that is how they get their names.

Useless tools.

[Post and beam]

1 minute ago, SteamyTea said:

clear cut

Define please

[Sealo0]

8 hours ago, Nickfromwales said:

Cheers. 2.5 would be huge, prob 1.0 or 1.5?

 

OK, my fears of them being 12v is now quashed, so the extra cable run may out of the window (for dealing with the voltage drop) but……
 

Next thing is, I have a pair of LEDs in my living room, wall wash, and these also the same thing; the second one is slowest to come on but is always the first lamp to blow. I have a Varilight dimmer (from TLC Direct iirc) and the dimmer AND lamps are both ‘dimmable’. 
 

If I put a switch on in place of the dimmer, problem goes away. Can you try this please? Turn off the power, put both wires in the switch into a connector block, then have someone else put the power back on / off and report the results plz.

 

Mine don’t ‘blow’ as quickly as yours do but you’ve got a longer circuit. 

Hi Nick.

 

Other duties are going to keep me away from this till the weekend, so will get back as some as I can. 
Also thanks for everyone’s comments.

 

I don’t care if it’s a bulb or a lamp, when they’re dead, they’re dead. 
 

will get back asap. 
 

regards 

 

Mike

[SteamyTea]

6 minutes ago, Post and beam said:

Define please

Do a forum search, I have specified the difference before and it saves totally detailing this thread.

[Post and beam]

20 hours ago, SteamyTea said:

Do a forum search

Its not that i dont know and need to search google. I believe the more closely you look the less clear the distinction appears.