where can i get solar powered led’s please?

[Chris Timmermans – Neon]

Have a word with John Lyons he’s got a few posts on the board knows what he’s talking about with Led’s.

Regards
Chris

[John Lyons]

Hi David, (Thanks Chris)
Can you be a little more specific, what are you trying to achieve, Why solar power to generate even low lumen output from an LED you require lots of Solar power modules!

LEDs & Power!
LEDs are different from conventional lighting systems in that they are electronic components with specific power needs. If the power is wrong, the lamps can burn out or the fixtures in your lighting system will produce light of varying brightness. Why? LEDs require current limiting. For example, if you connect an LED directly to a battery it would burn out because it tries to suck out all the power it can. To limit the current, all LED circuits need a limiting device in line with the LEDs.

There are two types of power supplies, regulated and unregulated:
• Regulated, constant current power supply – This supplies a specific current to the fixture, and the units are rated by their amp output. For example, a 500ma power supply will provide exactly 500ma, but to do this, it may have to raise or drop the voltage. In this example, the fixture needs to be designed with enough LEDs that it draws 500ma of current.

• Regulated, constant voltage power supply – This supplies a constant voltage. For example, a 12 volt, 500ma power supply will provide exactly 12 volts regardless of the current draw, whether it’s 100ma or 500ma. Since the voltage varies, a limiting device, such as a resistor, is required on the LED circuit board.

• Non-regulated (linear) power supply – This requires that the LED fixture be designed with power regulating circuitry. A 12 volt, 500ma power supply provides 12 volts with a 500ma load. But, if the load is only 100ma, the voltage can rise to 18 volts. 200ma loads can bring the voltage up to 16 volts. So depending on the current load, the voltage would change.

If you want to understand how efficiently Solar Power can drive LEDS, buy some from B&Q and put them in your garden, then try to read a book with the light from the B&Q solar powered garden lights……. See what I mean…..

On the other hand you might have a budget of 1,000,000 and try to engineer a solar powered regulated PSU…… Cool Project.

[Chris Timmermans – Neon]

Expertly Answered John :appl: :appl:

Regards
Chris

[David Feetham]

wow…..erm ok..lol

I’m trying to see if i could slightly illuminate an exterior sign. I dont want it to be massivley bright but just glow slightly. so if it was a dark night the sign would be visible…does this make sense???

the sign is only going to be around 600mm x 400mm.

let me know if this is do-able

thanks guys

dave

[John Lyons]

Any comments Chris.

[Chris Timmermans – Neon]

B&Q comes to mind!!!
It’s not going to work at night if its solar powered, than less you use a solar powered battery charger, then run your led’s off the battery…..

quote :

if you connect an LED directly to a battery it would burn out because it tries to suck out all the power it can. To limit the current, all LED circuits need a limiting device in line with the LEDs.

Regards
Chris

[Robert Lambie]

just wanted to say i personally appreciated the in depth answers from you so far john, excellent mate. I’ve am learning from your replies myself. 😉

[John Lyons]

Nice one Chris spot on (if you know what I mean).

Putting my commercial hat on for a second…. I haven’t come across any S.P. LED Tubes…. That’s not to say they don’t exist but.
Companies tend to make products to fulfill a specific requirement.. I.E. They don’t make fixtures that slightly illuminate. SO I have some questions.

What’s your idea of "slightly illuminate", in lumens please?
Ah ok so it outdoors – what’s the ambient lighting and how does this effect your slight illumination?
Do you need the LED fixture to be IP rated?
SO you want it to be seen at night, from what distance 1 ft, 10ft, 100ft?
What Colour do you want the LEDs?
Do you have a budget for Custom manufacture?
OK How much of the sign do you want illuminated, i.e. the perimeter, the perimeter plus 20% of the total sign, or do you want the total sign illuminated.
What colour is the Sign? (LED colours have specific effects on the colours they illuminate)
What material is the sign made from? ( Will the Sign absorb, reflect or refract the light)
Have you worked with LEDs before? LOL…..

[Chris Timmermans – Neon]

Ha Ha!!!
Answer all them questions Dave in detail if you don’t mind :lol1: :lol1:
All about learning on this site, I think you may need a wind turbine Dave plenty of wind on the east coast so I’ve heard Ha Ha!!

Regards
Chris