A silly question about solar panel

Hello all!

I know that a solar cell is a current source that within certain limits delivers constant current irrespective of the load. So let's assume I want to connect a LED consuming 20 mA to a solar panel. My question - can I connect this LED to a solar panel that delivers NO MORE than 20 mA? And if I connected it to a let's say 80 W solar panel delivering 3.5 A would it simply burn?

Once again sorry for this dummy question.

gusts

I know that a solar cell is a current source that within certain limits delivers constant current irrespective of the load

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Hi Gusts
No that is not a current source ! that is a limited voltage source ! it means it's current can't exceed from an special value but it can be lower than that ! .

a let's say 80 W solar panel delivering 3.5 A would it simply burn?

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Why do you think like this ?
Let me give you an example . consider that you are hungry . and your capacity is around two sandwich . if there are 50 sandwich nearby you , you can't eat all of them . you'll eat as you can ( two sandwich )
An LED is like a human ! it will receive it's desired current ! don't forget that a sandwich maker ( shop ) can make 50 sandwich but you can't eat more than 2 sandwich . so your supply can make 3.5 amperes . but your LED can't eat all of that !! :grin:
Best Wishes
Goldsmith

Without a current limiting resistor the LED will destroy it self. See the V I curves of LEDs

gusts said:

Hello all!
So let's assume I want to connect a LED consuming 20 mA to a solar panel. My question - can I connect this LED to a solar panel that delivers NO MORE than 20 mA?
gusts

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Yes, you can do so and there are chances that the LED does not get sufficient current to light up.

gusts said:

And if I connected it to a let's say 80 W solar panel delivering 3.5 A would it simply burn?
gusts

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The LED will burn for sure if you directly connect the LED to the 24V, 80W (approx 3.5A output) solar panel. We usually use a DC-DC driver or a charge controller in between the LED and the panel to limit and control the current. These devices are usually "constant current output" devices.

led require a certain amount of current but not more than that if the current is more than the threshold value i can assure you that the led will be burnt provided the voltage is sufficient enough

that is the power given to the led must be less than that of the power withstanding rating of an led

80 W solar panel delivering 3.5 A would it simply burn?

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a 23 volt solar panel delivering 3.5 A, SURE, it will be blown before you know. adding a limiting resistance will make a change. a 2.2k will do.

gusts said:

Hello all!

I know that a solar cell is a current source that within certain limits delivers constant current irrespective of the load. So let's assume I want to connect a LED consuming 20 mA to a solar panel. My question - can I connect this LED to a solar panel that delivers NO MORE than 20 mA? And if I connected it to a let's say 80 W solar panel delivering 3.5 A would it simply burn?

Once again sorry for this dummy question.

gusts

Click to expand...

You must limit current which flow through led.