Converting 12v lights to LED SMD

[Bailey]

CARAVAN LIGHTING

A GUIDE TO CONVERTING LIGHT BULBS TO 12 V. SMD UNITS

As Wife and I go to CL's, and many without hook ups, I did a bit of research into saving the Amps. My caravan lighting was the first thing to modify and below are some of the results of my work. Enjoy........

LED SMD units consume approx. 90% less power than bulbs for approximately the same light output.

SMD is the name for surface mounted diodes or a name similar. There are many. Basically, what this means is that the SMD is flush mounted on to the circuit board. They are usually a yellow colour in appearance.
They can usually tolerate voltages up to 14 – 15 volts.

SMD is the relatively new type of LED with better performance all round than the 'old' type, which are noticable by two pins sticking out of them.

To begin with though, you might have wondered,

How to measure the light output of a particular bulb.

The best measurement of light output, and generally the accepted way is the lumens measurement. Wattage is the power consumption ONLY
-but this might help :-

A Lumen is the TOTAL light output. 1 watt brightness = 20Lumens.

Dont forget that a lumen value measures the TOTAL light emitted by a bulb, so if you collected ALL the light emitted by a 40 watt incandescent bulb and put it into a narrow beam, it would fry your eyeball.

So, therefore, if you had a 800 Lm SMD it would be too bright for normal use.
400 LM is the most you would ever want to use for conventional uses.

Even this simple way of determining the total light output is not plain sailing as all that, and there are many other factors to be considered to obtain an accurate figure, but, to keep it simple, when choosing any type of bulb or SMD unit, look at the lumens figure.

An example of a Halogen bulb and an SMD unit is :-

Halogen-----------------------------------SMD
12v…………………………….……….......................12v
10 watts ………………………….…... ..............1. 8 watts
100 lumens ………………………….. ..............90-100 lumens.

In the example above the wattage is the power consumption. Vastly different!

Changing the bulb to SMD necessitates you to determine the wattage of the bulb. You will then have to look on E-Blag for that bulb and have a look at the specifications below the illustration to discover the lumens figure.

It is then a simple matter to look up SMD units and choose similar lumens.

I must stress here that there are many other factors to take into consideration, which is a another subject altogether.

What type of bulb holder do you have?

A very good place to see the different bulb holders is to Ask Jeeves, and search :-

holt 2 brochure

Scroll down to see the caravan types.

Click on this useful link :-

http://www.mycaravan.org.uk/LED%20Lighting.html

These sites show bulbs and bulb holders so you can identify the different types.

The simple way to obtain an SMD is to take one of the bulbs you want to replace to your local electric shop and ask them if they can get an SMD alternative. They should be able to, if they dont keep them in stock

The SMD's don't get hot. You can handle them even though it has been on for over an hour, and they have a reported life of 50,000 hours.

Once you have identified the type of bulb holder you have (Eg G4 type), go on to E Blag and search for SMD G4, SMD 12v, SMD festoon or similar, and have a look for the SMD unit you require, eg. GU10 - G4 or SMD festoon (Festoon for car interior lights (Measure the length) - beneficial for light and power saving).

UK supplier - Click the link below :-

http://www.baddiethepirate.co.uk/index.htm

The cheapest SMD units are on E Blag from Hong Kong, (G4 - £2 each Inc postage (At time of writing)) and thats where I bought all mine, and they are good. UK prices are usually double plus that, but have a good look around on the net.

For overhead G4 bulbs eg Bailey Dome lights and flush mounted spot lights, choose a G4 SMD. There are SMD's that emit a bright white light (Colour temperature 5500K), and those that emit a warm white light (Colour temperature 2800 to 3000K). I bought one of each to experiment with. So if you want the warm white SMDs then check specifically that is what you are ordering and / or look for the colour temperature. Perhaps it might be advisable to choose the cold white type for dark or work areas and reading spots, and the warm white type for the lounge mood lights.

Click the link below to view an example of a bright white G4 SMD.

http://cgi.ebay.co.uk/G4-24-3528-SMD...item4155f7a262

Cheap too - but you will have to wait a week or two for delivery from Hong Kong.

One note of advice. I have found the best way of fitting the above example is to insert the pins into the holder and then apply pressure to the bottom of the SMD near the base where the pins are, and bend the SMD to the right position. If you do it any other way, the solder joints are liable to break - which is not a problem if you are handy with a soldering iron. Some G4's have vertical pins on the back of the unit, so you will not have to bend any pins - just plug the SMD in.

SMD units have a full wave rectifier on it so its not polarity conscious, in other words, plug them in any way.

For those of you that want to modify overhead lighting in car or caravan, a dome light is a good modification which use G4 bulbs / SMD, but be warned, the normal type bulbs get very hot.

See the link below :-

http://www.bailey-parts.co.uk/Produc...Number=1010017

These dome lights have a three way switch.

Position 1. One bulb
Position 2. Off
Position 3. Two bulbs

These domes come complete with bulbs, switch and wiring.

I usually go to CL sites without hook ups, and I changed all lights to SMD's to save battery power.

With ALL my old normal bulb lights on, I would consume 11.83 amps.

On SMD units, I consume under 2 amps. WAY TO GO ....................

Staggering difference in power consumption - is it not?

Usually, no modification is required whatsoever to the caravan wiring and no additional electronics are required, and as long as the SMD type is 12 volts, the change over should be - remove bulb and replace with the SMD unit.



What size you should fit?

The simple answer to that is an SMD which fits the holder.

Thus, saying that, you can get different size SMD's to fit in the same holder. Again, just to make sure - visit your local electric shop or
E-Blag and have a look. E-Blag maufacturers usually give the dimensions in their adverts.

As an addage - 12v. SMD lights will not work with a dimmer switch - YET - and for interest :-
you can now buy

230v SMD LED's that are dimmable.

I use them in my overhead spots in the kitchen. My energy saving bulbs kept burning out. They might have been ‘energy saving’, but it was costing a fortune to replace them - my SMD's last FAR longer and are cheaper to buy and run. See the link below for expensive UK prices (£10 plus) :-

http://www.energylightbulbs.co.uk/ca...FYEOfAodeTjW7A

and, as before - cheaper on E-Blag from Hong Kong. (£3.68 Inc postage) Click the link below :-


http://shop.ebay.co.uk/?_from=R40&_t...All-Categories
I have included a couple of pics of a modification.


Regards Pete.

[Pandora]

Led light bulbs have a longer rated life than fluorescent and Incandescent bulbs. They last around 130 times longer than Incandescent bulbs and 10 times longer than compact fluorescent bulbs. Also as they are made up of plastic, they do not get damaged as easily as Incandescent bulbs. Due to the plastic surface, they sustain grating and bumping.

[danielo]

Great guide, thanks for sharing that with us.