# Solar panels with 100W led

Discussion in 'LEDs and Optoelectronics' started by NVZN, Jun 21, 2017.

1. ### NVZN

9
0
Dec 17, 2016
Hello, i have a solar panel 5W 12v (seller said that)

And here is the product

I Tested it with super hella bright LED 100W. Its so damn bright.

And i was surprised my solar panel only got 6V, idk the seller mistaken the voltage or what? Should i take refund?

Or i must use direct sunlight to it? (b.. But my led is damn bright)

2. ### Audioguru

2,580
585
Sep 24, 2016
The solar panel has a maximum allowed rating 5W at 12V. Then its maximum allowed current is 5W/12V= 0.417A.
It looks like you are not limiting the current to no more than 0.417A then either the LED or the solar panel (or both) will soon burn out.

Of course a solar panel is used in direct sunlight.

3. ### NVZN

9
0
Dec 17, 2016
Do solar panel will burn if i just connect to the multitester??

Wait, solar panel if not limit the current will burn? Didnt from other source says "if it reached its maximum, and that is, nothing improvement, its the max"

4. ### Audioguru

2,580
585
Sep 24, 2016
If you try to test the maximum current from the solar panel in direct sunlight then the multimeter is a dead short circuit and the current will be much higher than the maximum allowed current.

The datasheet for the solar panel will show its voltage drop and its current increase with lower load resistance. There is a point where the power output is maximum which is thre voltage and current of its rating.

You did not post the datasheet for your 100W LED for us to see its forward voltage and recommended current.

Here is as graph of a solar panel when loaded:

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5. ### BobK

7,624
1,654
Jan 5, 2010
Since you two are talking past each other...

AG - He is shining his 100W LED on the solar panel and complaining that it produces only 6V.

NVZN - The LED may be bright, but it is unlikely as bright as the noon sun.

Bob

6. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

25,191
2,692
Jan 21, 2010
And it is perfectly acceptable to short the output from a solar panel.

You can't destroy them that way and the won't produce too much current.

A LED with a higher resting than the panel can only be damaged if it is connected backwards or it is poorly heatsinked and gets too hot.

Audioguru needs to stop giving advice where he clearly lacks understanding.