LED nightlight

[Clair]

Hi

We're in the process of listing all our "wish-list" for a bedroom in the attic conversion.

Some items are "must have", some are "would like to have"...

On my wish list, I have thought of a wall fitted diode at floor level, acting as a nightlight by each doorway.

I have to see if this is possible, but where would I start looking for them?

[Wozza]

Clair

I don't know if these would do, but at Castorama, and probably other Brico places, you can buy mini halogen type lights - they are about the size of a euro coin. There are two types - one fordecking floorboards andthe other for internal use, normally on ceilings to give a 'starry, starry night' effect. I guess you could buy a pack of these and link them together so they were all on at night. Available in white and blue, I think and I have seen them in packs of five. Thought about using them up my staircase.

Warren

[Ford Anglia]

A few to look at here:

http://www.screwfix.com/app/sfd/cat/cat.jsp?cId=102500&ts=92684

Dunno if they would be available in France yet, halogen lights wer about 5 years behind the UK.

I'd avoid tiny halogen bulbs too, they are dear to replace and don't last long[:(]

[Clair]

Thank you both for the replies.

I am slightly flumoxed though, as I do not seem to find a wattage rating equivalent for any of the lights I've been looking at. As they are meant to be nightlight, I need them to be rather dim. Some of these are described as 'very bright'.

I've been looking at Conrad in France and this is much more involved than I thought!!

I think it might be easier to stick to plug-in nighlights.... unless someone knows better...?

[darnsarf]

If it is a nightlight you're after, then you probably need to look at a single LED with a chrome/white/black housing with flush fit into doors, skirtings and doors. They are very cheap and http://www.ultraleds.co.uk/product_info.php?cPath=25&products_id=118&osCsid=9f05544fe48cc5333b26e1670d192a4d has quite a few examples. The problem is often voltage - most LEDs work on less than 24V (so transformer or batteries are needed) though there are I think some that will work on domestic voltage, though these seem to be clusters of LEDs (using same fitting as halogens) thus producing more wattage than you probably want. Many LEDs that are 'white' are often blueish in hue so best to buy a few different types to check first. Some even have variable switches so you can turn a 10 LED (bright) cluster into a (glowing) 2 LED cluster. Hope this helps. You'll find plenty of suppliers on the internet and the LEDs themselves cost only pennies each - its the housing/fitting that costs. Bulbs last for about 50,000 hours and, unless it is a cluster unit, need to be entirely replaced once 'blown'. I've fitted (12V ones) all over my boat, including flush ones into the steps into the saloon. All very simple (and I'm no DIYer!)

[darnsarf]

Sorry - just re-read your post. An LED may well be described as 'very bright' but this is a relative term (i.e. compared with other LEDs) Provided it is not a cluster of loads of LEDs, no single LED should be so bright to dazzle (and their actual wattage is minimal, it's the equivilent wattage that is often referred to). You may even find that the brightest (single) LED is not bright enough. Look at a string of LED fairy/christmas lights and you'll see what I mean. The less bright LEDS tend to be bluer than the superbright ones.

[Clair]

Thanks for that clarification. It makes more sense now!

I will pass on all comments to He-Who-Does and we'll see if these make it to the "must have" list!

[Gluestick]

You can operate LEDs on AC in point of fact, but a "Normal" LED will suffer from restricted light output as the current alternates.

One Korean semi-conducter manufacturer only recently announced a new range of dedicated LEDs for AC operation.

http://www.seoulsemicon.com/eng_seoul/English/popup_content.asp?news_idx=8

 

[Btuckey]

[quote user="Gluestick"]

You can operate LEDs on AC in point of fact, but a "Normal" LED will suffer from restricted light output as the current alternates.

[/quote]

Not strictly true Gluestick!  Most commercially available Light Emitting Diodes emit light when around 1.4 to 2volts (Vforward) is placed across the device.  The maximum reverse voltage (Vreverse) is 5volts.  If you exceed this, the junction will break down and destroy the device.  If you are running the device from 2volts AC I agree that it will work albeit with reduced light output.  However, most devices are run from much higher voltages with current limiting resistors.  This limits the current in forward mode but will be too high if the polarity of the supply is reversed.  The ‘usual’ modus operandi is to place a forward biased ‘standard’ diode in series with the LED.  This will have a Vf of around 1volt and a Vr of 50volts (1N4001)

The commercially available AC LED devices contain a bridge rectifier to ensure even brightness over both phases.  

Brian 

 

 

[Gluestick]

Thanks.

I was searching here: http://www.gizmology.net/LEDs.htm

The bit about halfway down seems correct? (Running LEDs from an AC power source?).

Also looking at other sources, since I too have a couple of projects to utilise high-output LEDs for AC supply.

 

[Btuckey]

[quote user="Gluestick"]

Thanks.

I was searching here: http://www.gizmology.net/LEDs.htm

The bit about halfway down seems correct? (Running LEDs from an AC power source?).

Also looking at other sources, since I too have a couple of projects to utilise high-output LEDs for AC supply.

[/quote]

Indeed, they’re talking about an AC supply voltage where the negative going voltage peak is just under Vr; i.e. 5 volts.  Perfectly true in theory but rarely achievable in practice.  This sort of voltage regulation costs money.  Much cheaper to employ a ‘wallwart’ or similar where the output AC voltage wanders all over the place and put a diode (less than 1p in quantity) and resistor in series.

As a matter of interest, have you seen the following:

http://www.goodworkint.com/leds8_ingles.htm

http://www.vishay.com/leds/

http://www.stanley-components.com/en/index.cfm

http://www.superbrightleds.com/led_prods.htm

http://www.etgtech.com/2006/html/xlamp.htm

http://www.rapidonline.com/productinfo.aspx?kw=728005&tier1=Electronic+Components&tier2=Optoelectronics&tier3=Power+LEDs&tier4=SMT+XPower+LEDs&moduleno=71503

http://www.rapidonline.com/productinfo.aspx?kw=56-0102&tier1=Electronic+Components&tier2=Optoelectronics&tier3=Power+LEDs&tier4=Linear+light+module&moduleno=75838

The latter would be ideal for doorway illumination if you can rebate the strip and cover with a piece of clear plastic.

Brian

 

[Gluestick]

Thanks, Brian

Useful URLs, too.

 

[Btuckey]

[quote user="Gluestick"]

Thanks, Brian

Useful URLs, too.

[/quote]

Glad to help.  I forgot about this one which you probably have seen:

http://www.thelightbulbcompany.co.uk/

 

LED lamps are near the bottom.

 

Brian