Forum Topic

Light bulb moment - of despair

Just a reminder of how relatively simple and intelligible choosing a light bulb used to be:-"An incandescent bulb typically consists of a glass enclosure containing a tungsten filament. An electric current passes through the filament, heating it to a temperature that produces light.Incandescent light bulbs usually contain a stem or glass mount attached to the bulb's base which allows the electrical contacts to run through the envelope without gas/air leaks. Small wires embedded in the stem support the filament and/or its lead wires.The enclosing glass enclosure contains either a vacuum or an inert gas to preserve and protect the filament from evaporating." (With thanks to Bulb.com)Bulb, filament, inert gas. Now:-https://www.homebase.co.uk/ideas-advice/lighting-and-electrical/light-bulb-buying-guide

David Ainsworth ● 2563d14 Comments

But once you've made the choice and changed the bulb hopefully you won't have to drag the stepladder out again for several years!

Philippa Bond ● 2563d

OTT and I don't believe any of those lifespans.

Sue Hammond ● 2563d

I was a bit puzzled by that description but they really mean correlated colour temperature for non incandescent bulbs like LEDs. And they've ignored the different spectra from non incandescent light sources, so it probabilities should be read with the following two links. (There many be better ones but these were near the top of Google.) https://en.wikipedia.org/wiki/Color_temperaturehttps://uk.comsol.com/blogs/calculating-the-emission-spectra-from-common-light-sources/Personally, I just look at the Lumens and Watt equivalents, Philippa's probably got the right idea and I agree with Sue's cynicism about life spans. I suspect there's a difference between the theoretical longevity and how long the manufacturing process determines their life. Otherwise they'd go out of business!If I want to worry about Kelvins and black bodies, etc I'll hop onto the Slooh remote telescope and look at some stars 🙂

Michael Ixer ● 2563d

It seems to be impossible to buy the same bulbs twice.I agree with Sue about the longevity claims.  However they do expand the claim in the small print.  Marketing has a lot to answer for.  I mean how they can tell what is a normal use of a lightbulb?  I do tend to write on lightbulbs the date that I change them.  Sometimes it is surprising how long a life they have; sometimes how short a life!  Interestingly there are some bulbs which don't like working in the cold.  I used to find it quite satisfying choosing and changing light bulbs but even without going to David's lengths I've had to lower those expectations to just being able to see and not having to drag that ladder up the stairs!

Philippa Bond ● 2563d

The curly fluorescent light bulbs were sold at a higher price because of their promised extended lifespan and money saving lower consumption. Unfortunately this was never put to the test and our money was wasted because newer LED bulbs came out after a year or so, costing even more with even greater claims being made for them. Progress?! Hmm!

Peter Evans ● 2562d

I switched out all my bulbs, first for compact fluorescents, then for leds. The house is bright, no-one complains and my lecky bill is down by about 1/3Some bulbs fail early (always the circuit board) but most seem to last years

Sean Hodges ● 2562d

"Some bulbs fail early (always the circuit board) but most seem to last years"On Youtube there is a chap showing how to repair failed LED bulbs.

David Ainsworth ● 2562d

GLS bulbs typically were said to last 1,000 hours - mostly they did but many did not. They are wasteful of electricity and were prone to sudden failure. Mini-Flories do last somewhat longer but are prone to dimming naturally with time, on the plus side they are not prone to sudden failure but tend to dim somewhat giving warning of impending darkness.What is important when selecting an emitter is 1) the type of mount (bayonet, ES, SES etc) 2) the wattage and 3) the desired colour temperature. The last two being the most relevant when considering the desired lighting level and ambience.Hope this helps if it hasn't added confusion into what should be a relatively simple subject.

Clifford Cowell ● 2562d

LEDs are great, but when I recently bought a really low wattage bulb for my hallway and the nice guy in the shop on the High St said it was "daylight", blimey it certainly was!!  I had to get one that was same wattage but much creamier in colour.

Bunny Payne ● 2562d

You only really want daylight bulbs in kitchens and bathrooms, if anywhere. As for repairing a failed LED bulb — I am a dab hand with a soldering iron, but opening these things up tends to damage or destroy them (I tried out of curiosity), and they aren't that expensive — they keep getting better and cheaper with time.
Screwfix currently have 100W-equivalent (1521 lumens) LED bulbs at £12.49 for a box of 4 (£3.12/bulb). These are nice and bright. https://www.screwfix.com/p/sylvania-bc-gls-led-light-bulb-1521lm-15w-4-pack/405gx 60W-equivalent (806 lumens) are £10 for a box of 5 (£2/bulb) https://www.screwfix.com/p/lap-bc-gls-led-light-bulb-806lm-9w-5-pack/3118t

Sean Hodges ● 2562d

Oops, picked the wrong set; https://www.screwfix.com/p/lap-bc-gls-led-light-bulb-806lm-9-5w-5-pack/5894t These are the warm white ones

Sean Hodges ● 2562d

As a dab hand with DIY, you may appreciate this 43 second bit from "Malcolm in the Middle":-"Hal fixing a light bulb"https://www.dailymotion.com/video/x2gp98t(Hal played by Bryan Cranston)

David Ainsworth ● 2561d

Breaking Bulb!

Sean Hodges ● 2561d

Quite a range, Mr Cranston has.

David Ainsworth ● 2561d