I don't think this is a critical question,
but I thought I'd check anyway.
I have a bunch of 6 volt, 50mA solar
cells. I'd like to put them all in parallel.
I don't think this is a critical question,
but I thought I'd check anyway.
I have a bunch of 6 volt, 50mA solar
cells. I'd like to put them all in parallel.
Shouldn't each of them run though a
diode, so the cells are isolated from each
other? This is really a shot in the dark,
because I can just run down to Radio
Shack and pick up something. BUT do
you guys have any particular
recommendations?
Also, because of life stuff, all my Part 15
projects are now on slowed waaaaaaaay
down for a while. So the last
thing I want to do is just get those
panels running and then set them aside.
That's why I want to pick up the diodes.
I will still be here on the board putting in
my comments, because, quite frankly,
I love this place.
Bruce, MICRO1690/1700
P.S. Projects that don't require any money
will keep moving veeeeerrrrrrrry slowwwwwly.
Yes...you will want to isolate each solar cell with a "steering" diode. You will also want to add a final "steering" diode at the final output of the array.
The steering diode helps to protect each solar cell from their neighbor in case one flakes out or short out, as well as prevent any potential of reverse current flow. If one cell shorts out, the diode will prevent that cell from shunting out the entire voltage produced by the others. You will simply notice a drop in total voltage produced by the voltage produced of each cell.
So if each cell produces 1 volt and you have 10 producing 10 volts and one shorts out, the diode will prevent that shorted cell from shorting out your entire power buss and only reduce by 1 volt due to the dead cell.
Each diode will have a voltage drop in of themselves...approx .7 volt. Since solar cells actually can produce more voltage than their labeled rating states, a mere .7 volt loss is rather irrelevant. Even a 1.5 volt solar cell in full sunlight can produce as much as 3.5 volts or more with no load.
I also suggest you add at the final output a voltage and current limiting circuit. This will ensure that any voltage variance by the cells due to sunlight change is minimized at the output.
Series them to produce more voltage. Parallel them for more current. Two 10 series tied solar cells producing 10 volts each can be tied in parallel to double your current capacity. Its just like connecting two batteries in parallel to gain more current capacity.
Have fun!
RFB
... or maybe bedazzled 😉 You have 6 volt solar cells? Or do you mean 6 volt solar panels? 6 volts is a lot for a solar cell.
I thought I was the one who was dazed
and confused! (By the way, I'm sorry 1
missed your live broadcast.)
Anyway, I don't know much, but I can
tell you that I have bought a bunch of
solar cells at Radio Shack. Also, a few
were given to me. They are rated at
6 Volts/50 mA. I have already run a
C Crane transmitter off of them in
full sunlight. The object is to build
a simple solar powered repeater, which
is actually on another thread.
Each one of these cells is 6 volts/50mA.
One of them costs $14.95 at Radio Shack.
Each one is close to the size of an IPOD.
Some people have come on the solar powered
thread(s) and made good suggestions on this
subject, such as, RFBurns, above.
So I could be wrong, and I'll check - but I
believe those are the specs.
Best Wishes,
Bruce, MICRO 1690/1700
For $20 I bought a solar experiment kit at Radio Shack for my Grand Daughter (really its for me.)
Among other items included is the solar pannel. It contains 3 cells each capable of 100 ma. They can be wired series or parallel so you can have 4.5 volts at 100 ma or 1.5 volts at 300 ma.
Looked like a better deal and she had some fun learning about solar cells. On the plus side, when she tires of it I can run my portable radio on it.
That helps to understand. It functions sort of like a solar cell, but it's actually an encapsulated set of cells, you can see them in the picture.
With poor knowledge (compared to Mr. Burns) I agree the diodes is a good idea, just as with good Christmas lights. I wonder if you can build a controller for the final output.
What about, instead of using as a relatively unreliable direct power source, you instead hook them up to just charge a battery, and run your repeater off that? That would ensure a much more constant power source, and your repeater could remain on indefinitely.
... Just thinking out loud, so-to-speak 😉
This is great stuff ... I'm inspired to start building my own solar power source! I always liked the idea of making free power. There are farms on the island that sell power to OPALCO. If they don't need it, OPALCO in turn sells it back to BPA, and all of us consumers benefit. It's a win-win deal.
Use a photo cell and an RC car or airplane servo and a differential amp circuit and you can make a mounting assembly for the cells to track the sun as it moves across the sky for optimum performance from the cells. I made one several years ago and still use it today. Its portable so I can take it on camping trips. I also have one mounted on the top of my slide in camper and one on my RV to charge the 12 volt systems. Replacing all of the standard light bulbs with super bright LED's, you can drastically reduce current draw and have plenty of light at night...all night.
RFB
I love the description of the sun tracker! That would be the coolest super good idea to make the solar collection "intelligent" so it "stayed tuned" to the sun's location.
It's a must have for home made power!
Yep...I came up with that idea years ago when I got tired of always having to adjust and reorient the assembly to be looking directly at the sun.
Ya Im lazy. 😀
RFB