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Hi,
I've upgraded my fw flipper from 3s to 6s, the problem is that I forgot about the led strips which are only rated for 12v. To stop them blowing up I wondered if I could put a resistor in parallel with the hole strip, if so how do I calculate the size of resistor?
As a side note- I tried plugging in the removable link (forgetting about the LEDs) and there was a lot of sparks and smoke from the deans connector melting the contacts- could this be because of the LEDs?
Thanks,
Max
I use 12v leds on 6s all work ok never blown up either :)
u will get a spark on the link thtas the lipo 6s and normal
That's good to here about the led strips, I know I should expect some sparking but my fingers and the surrounding area where covered in black powder, litterally half of the metal contacts on both sides completely melted!
I'll replace it and see what happens, maybe I just need to plug it in faster!
Well, I thought I'd temporarily swap the removable link for a 30A switch, but as soon as I switched it on it smoked and fused together!
I am now pretty sure the batteries are being shorted when it is turned on :( across the battery terminals there is a resistance if 0.5 ohms when not turned on and with the motors unplugged. I think that would make an instant current of nearly 50A so that could cause all that sparking. Any one know what kind of resistance there should be across the terminals? I imagine it should be very high as the only route for the electricity should by the LEDs which should have a high resistance.
A LED has a fairly low internal resistance, that is why LED's in "ready to use" form have some form of current limiting, of wich a resistor is the simplest form.
What I read here, John had a LED strip with a circuit for variable voltage input, and yours didn't. To make a long story short.
POOF. I think your LED's are dead.
They were these led strips:
http://www.giantshark.co.uk/high-den...-p-404318.html
So have some resistors in them to make them work on 12v, but 24v may have blown them?
Straight from the page you give us.
In other words, those leds needed an input between 7V (probably as low as 6V) and 13V. Not 22.2VQuote:
Large voltage input range up to 12V DC! (Great for 2-3S Lipoly)
I almost garanty that 24V will have blown them, and I'm not an electronics guy.
That's exactly what I was worried about, I don't think there broken yet (only been run for a less than a second) I've tested them with a multimeter and they seem ok. But is there anything I can do other than buying a 24v version?
Power them from a seperate battery, a 500maAh 3S will do nicely.
Voltage regulator
Its easy, take your 12v strip and cut it in 2 bits both same lenth, then wire both together in series. Worked for me in toxic for a few years. My 2 x 12v strips run on 30v quite happily.
That's a brilliant idea! I've already got it in 2 strips in parallel so dead easy to change it to series. I also think I've solved my shorting problem so may have time for a test run tomorrow, it should be much faster now with 24v, 150mm wheels as ive fixed the half throws from the mixing.Quote:
Originally Posted by terry