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Topic: Arduino Lightsaber (Read 407517 times) previous topic - next topic

JakeSoft

On the whole it's not recommended to charge multiple Li-Po cells at the same time without proper monitoring and cell balancing circuitry. The short explanation is the cells don't all drain and charge at exactly the same rate and if one cell fills up first, it can cause it to start draining into the emptier one which is a situation to be avoided at all costs.
This jives with what I have read as well. The pre-made multi-cell high capacity packs  have PCBs that do this load balancing across the cells, so you have to charge the cells individually otherwise.

billpealer

#556
Jan 24, 2016, 07:27 pm Last Edit: Jan 25, 2016, 03:04 pm by billpealer
On the whole it's not recommended to charge multiple Li-Po cells at the same time without proper monitoring and cell balancing circuitry. The short explanation is the cells don't all drain and charge at exactly the same rate and if one cell fills up first, it can cause it to start draining into the emptier one which is a situation to be avoided at all costs.
i have/use a balancer for the 14560 packs shown in my post with the 3D printed sled. I am a green horn with arduino, but i have been making my own 2+ cell lipos/lithiums, for the better part of 10 years. i hate doing it.  making packs is a hassle and a half that THAT is something to avoid at all costs :).  and while you don't need balancers, at all. period. you don't.   the real reason to use a balancer is if one of the cells is on its way out, a 7.4v charger will keep pushing voltage till it gets to the right 8.2v smart charger cut off point.  if one of the cells is bad, the good cell will over charge and puff up, and shoot burning hot exposed lithium.  hot enough to melt aluminum. or what ever toy/gizmo you have the pack in. and because each cell is charged independently. it may decrease charge time.  balancers charge faster/safer.  not any better. i wish they made them for my 7.2v packs for my 1:10 cars.  A NiMH pack with a dying cell will get HOT during charging.  if they had balancers, just the cell that was not as good as the others would get hot.  if the cell was dead, the charger wouldn't work.  Same with Lipo. With Lithium, A dead cell is safer than a bad one.  and if you know the order of cell charging in a balancer, you can replace the bad cell. the balancer will simply shut off (maybe with an indicator light) when it gets to the bad cell.
they are for Lipos mainly,
for 14560 and 18650, or any pcb cells,... 99.9 times it's whatever. Unless you're dell computers.  they must buy the worst 18650s. they are always int he news for melting people's laps.   a 7.4v lithium smart charger. read the specs, make sure the auto shut off is somewhere tween 8.2 and 8.4v.  some 7.4v smart chargers only push 7.4v (found that out the hard way) , which will charge your batts to about 30% capacity.

JakeSoft

i have/use a balancer for the 14560 packs shown in my post with the #D printed sled. I am a green horn with arduino, but i have been making my own 2+ cell lipos/lithiums, for the better part of 10 years. i hate doing it.  making packs is a hassle and a half that THAT is something to avoid at all costs :).  ...
Yeah, I agree. It seems like a giant pain to make your own packs and that kind of goes against the approachable nature I was hoping for with this project. You shouldn't need to be an EE to build one of these things. I'm certainly not. Let's keep it as basic as possible.

Thanks for all the info, Bill. I'm so glad you are part of this thread; I've learned a lot from your posts.

billpealer

Thanks for all the info, Bill. I'm so glad you are part of this thread; I've learned a lot from your posts.
ok... that's cool.
bool = saberon and MOSFETs changed my life.  :)

JakeSoft

ok... that's cool.
bool = saberon and MOSFETs changed my life.  :)
Haha! They'll do that!

JakeSoft

Page 7 Canobi and Jake refer to the USB WT as the 32pin version.  For anyone bouncing around. this may cause confusion when people start parts searching.  i am going to call for a correction of Canobi's post that kicked this off.,..

I should delete this post when post #95 is amended.

There are 3 types of WT

1- 16pin , no usb.
2- 28pin No usb
3- 28pin USB


no 32 pin versions.  and they vary from8mb - 32mb in memory.

I corrected post #97.

Canobi

#561
Jan 25, 2016, 04:12 pm Last Edit: Jan 25, 2016, 04:18 pm by Canobi
Post #95 also corrected.

billpealer


Protonerd

anyone hear of /try  these?

Quads?  10W  supper high voltage and uses a single Lens not a tri lens.

http://www.ebay.com/itm/10w-Cree-XLamp-XM-L-RGBW-RGB-White-Color-LED-Emitter-4-Chip-20mm-Star-PCB-Board-/231519043679?hash=item35e79c405f:g:PWYAAOSwPhdVGPkT

RGB+W  !?


Yes Sir, one of my TCSS sabers use this. I also intend to use 2 of them in my upcoming saber staff (powered by Arduino of course :) ).
BTW, in the TCSS saber I used only RGB, W was left unconnected, since I did not need it. But with the added fleixibility of Arduino based electronics, I will in future. And only one lens, that is right.

billpealer

Yes Sir, one of my TCSS sabers use this.
how's the brightness? heat? seams like 3500ma in the space where normally one LED lives is,..  cozy. tgtbt.

Canobi

Hi guys

Just a quick update..

I was really busy this w/e as it was my son's 13th and had a whole lot going on and etching didn't get a look in. However, I did spot something I missed which would have been a problem, fixed it, and ended up with two distinct versions of the board in doing so.

There's now a low volt board for 3.7v~5v supplies and a high volt board for 6.5v~12v supplies.

The issue was with the micro boost buck, a 7.4v delivery would just go and let all the magic smoke out of it and there just wasnt room to stick in another component so replaced the boost buck with an LM1117 5v fixed regulator which instantly reclassified the circuit for high volt while retaining it's WT power rail flexibility.

The buck is still present on the original file so that became the low volt board, the only real change on that one was to removed the redundant power rail from the RAW pin.

Talking of which, the little space gained by removing said redundant power rails was used to increase the size of the bridging pads so they're easier to solder.


JakeSoft

Hi guys

Just a quick update..

There's now a low volt board for 3.7v~5v supplies and a high volt board for 6.5v~12v supplies.


I like it and I think this makes more sense.

stinky1

Just another quick question about momentary switch ratings.

They come in 12v, 9v, 5v, 3v. prolly 6v too.   I plan to use two 18650 batteries.

So for a illuminated momentary switch,  what voltage rating do I use?

I know I need a resitor or a Dyna-Ohm to protect the LED.

Would 12 v be OK because it can handle all lower voltages?

Bought too long of a switch so I gotta get new one,  it was a 5v 16mm.

Neat it seems momentary,  and latching if you press it further.  Too bad it won't fit
in 1  1/4 sink pipe.

For that matter two 18650 are 1  7/16- 36mm wide, so they won't fit side by side in 1 1/4 pipe.
So they would have to be single stacked lengthwise.  Series or Parallel?

Now I see why the discussion on battery size. 

billpealer

#568
Jan 26, 2016, 04:16 am Last Edit: Jan 26, 2016, 04:18 am by billpealer
Stink, are they the 16mm momentary switches?  If so i recomend the short barrel version. not the 32mm one,... The shorter one. And get 12v.  They can handle more than 12v.  They are like 12v 20amp.  That's liket 200 watt. These sabers... The Most will be 10 watt. 

Treat the LEDs on them like stand alone.  Blue/green 3.2v 50ma.  Red 2.5v  50ma.  Resistors for that.

Jake, I'm glad you can look at those pcbs and contribute to it.  It all looks like Tron to me.

stinky1

Hey guys thanks for the fast response,  Ebay cart is awaiting.

Just to let you know I saw the RGB-W's as well,  but check these out!

http:/5x CREE XBD XB-D 9W white+red/red+green/Yello+green/RGB LED Light Emitter 7V/8V/www.ebay.com/itm/5x-CREE-XBD-XB-D-9W-white-red-red-green-Yello-green-RGB-LED-Light-Emitter-7V-8V-/222002233766?var=&hash=item33b05d41a6:m:mUmj13QzPcQeOcGyDw4a_1Q



Only problem is its 5 of them minimum.   Nice for you multiple unit pro builders.  Still its like 18 dollas for 5! Not bad :)

And thanks,  you talked me out of making a battery pack,  the thought of them gassing out in a sealed tube,  the blade shooting into the ceiling etc etc... lol!!  2x sled mounted in removable battery holders I already have.   Then I can take them out and store them in steel box.  I always charge batteries in a porcelain sink so if they cook off all I get is gassed,  no fire.  Just don't turn on the tap!

 

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