LED Lighting

[deejames]

In view of all the interesting posts about volts and amps and stuff recently, I would appreciate some opinions on this one .....
There are 230v LED bulbs available for around a fiver each which claim to give the equivalent of a 20W tungsten bulb, but which draw only 1.2W.
So .... if I use an invertor to convert 12v into 230v, and run 10 LED bulbs to illuminate the interior of my boat, I will be drawing around 1 amp. That's less than ONE 20W / 12V bulb. Assuming that the invertor is only 90% efficient, then broadly speaking, the current draw will be roughly the same.
So ..... I get 200 watts of lighting using LED bulbs for the same battery drain as 20W from conventional tungsten bulbs. I can also see how a small relay could provide automatic change-over when shore-power is plugged in. But - am I going to kill myself by having 230volts floating around in a damp salt-laden atmosphere.
Should I be getting out more ??

 

[LadyStardust]

why not look at 12V LEDS for internal , and even external lighting. A quick google on "12V LED Lights" returned http://www.ultraleds.co.uk/default.php?cPath=51
with some interesting LED lights.

 

[alec]

Sounds good - probably too good !


' Logic is the art of going wrong with confidence'

 

[Prospero]

No not too good to be true. I've fitted red LED lighting in the saloon and heads which is permanently switched on when at seaat night . Lighting very adequate, except I need close up red lighting over the nav desk. No damaging light coming up through the companionway and night sight is unaffected. The consumption of the three is about 0.7 amps. I am very happy and so are my batteries.

 

[jfm]

LEDs is sensible if you want to reduce pwr consumption but the 230v idea is madness. The insulation in your lighting circuits will not be appropriate for that voltage, and it would be highly dangerous. But as others have said, there are loads of LEDs suitalbe for 12v

The very cheapest idea is to buy the LEDs from Maplin or suchlike, and solder in a series resistor, and bug the LEDs inside your existing light fittings. Saves having to fit new lights, which might require different hole sizes etc. I have done this in several places. Typically £1 to £5 per lamp (the ultra bright whites can be nearly £5 each)

Calculating the series resistor is easy. Holler if you need the maths

 

[William_H]

I would be very interested to see the 240v LED lighting. Does it give as much light as a 20w lamp only because it is highly focussed? A 20 w lamp is omnidirectional and if focussed would give a very bright light. Stringing LEDs like 100 on 240v could be quite bright in the direction of light output and becomes very efficient because there is only one current limiting resistor thats unless they have a power conversion circuit of some sort. any clues? I think an inverter 12 to 240v would be inefficient. Will

 

[Guest]

If you look around you can find some good LED items.

I have just fitted a unit in the heads, it has six orange leds, runs off four AA batteries, and has a pir movement sensor.
Swtch is either off, on or auto

£7.99 from Tchibo, who have a stand in my local Somerfield.

 

[Gordonmc]

Precisely what I have done.
The arrangement is that when the master cabin light switch is thrown at the fuse panel all four ceiling comes come on with the LEDs. The original incandescent lights can then be switched on at each fitting for more light when needed.
I bought festoon 4xLED's from Ultraled and made up fittings out of the fuse holders in old 13 amp plugs, araldited onto plastic strips. These were wired into the feed and neutrals in the existing light fitting, upstream of the on /off switch.
The notion of using an inverter to convert to AC seems illogical to me. The inverter will waste more power than will be saved by using LED's. Use 12v ones.

 

[Alastairdent]

I've used LED lights a lot. Home-made, and commercial.

The home-made were fun to make - but you must add a voltage-limiting device of some sort. Otherwise your LED's will blow when you are charging your battery. They strobe in lots of colours then burnt out with a lovely sound.

Commercial - I've used 2 sorts. LED downlighters from B&Q - £11, can be recessed or surface mounted. Good quality, and very very good for lighting a small area. Suitable for Galley's or as a reading light over a chair.

The other sort is replacement LED bulbs for car interior lights. The interior light fitting are about 1.50 each, and you can get the bulbs for around £3. These are quite good for lighting a small area. Bright enough to read by and do general jobs. These bulbs are avail from auto shops, the sorts of places that sell fancy car trim.

The commercial sort come ready fitted with voltage limiting circuits. Having done both, I'd say buy commercial.

 

[pappaecho]

I have replaced most of the conventional "car type" bulbs with MR16 type 2 pin sockets.
These will take either 12 volt LED "bulb" arrays, or 12 volt dichroic spots, in 20 -50 watt range .

(The MR16 bulbs come from "low voltage" spots and cupboard lights which are sold with a 240 volt transformer, and are used in kitchens and bathrooms at home.)

There are also LED festoon arrays which will fit existing yacht type festoon fittings but produce no heat and the same amount of light for 1/10th the power consumption.

There are also 12 volt "led bulbs" which fit conventional car type fittings, and I have tested these, but they are highly directional. I thought of using them for nav lights but they are too directional to be of any use.

Somebody somewhere must be able to produce a 360 degree LED bulb that we can put on the top of the mast and forget, as the MTBF of LEDs is about 50,000 hours, which will see the boat off.

I like the LEd concept as it produces the same light for less than 10% of the power consumption, they last for a very long time, and if one LED in an array of 20 goes, you will not notice it... oh and they produce virtually no heat

 

[VicMallows]

The link in the second post of the thread list some 'mast' lights which are claimed to offer 360deg. , along with the other types you mention and many others. I'm tempted to try a white one as an anchor light.

Vic

 

[LadyStardust]

I have built a 360deg LED Anchor light, but have not had a chance to see how it works yet. I did hoist a B&Q garden solar powered lamp up a halyard last season while my boat sat at anchor on the mud/river. It seemed to work ok, as lots of people kept telling me I had left my lights on! It wasnt bright enough for real use, but it did get me developing a brighter version. I built a version using 12 LEDS aranged in a circle. One of the problems with LEDS is that the luminosity or received light is directly proportional to the angle of radiation/viewing. Often the very powerfull LEDs throw a very tight beam, often less than 30deg. There are lots of references on the web I can recommend if anyone wants to take this further, I know I would buy one, especialy if it was solar powered.