CF4.0 with 11.1v battery pack?

[8lade]

Hey guys, I just wanted to ask a quick question.
Will cf4.0 work with this battery pack or will it fry?
http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=2565

cheers

[Donnovan Sunrider]

From the stuff I recall, I think 7.4v is the optimum for CF to be happy.
I don't own one though, so I'm not speaking from experience.

I was looking at this pack (http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1209) as a possibility, but I'm not sure that would work.

[eastern57]

Hey guys, I just wanted to ask a quick question.
Will cf4.0 work with this battery pack or will it fry?
http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=2565

cheers

There's three things here that should be addressed:

- Obviously, yes, 11.1V is the recommended Max that Erv suggests. In other words, anything above that can't be assured, and may end up frying a CF. I personally wouldn't even push it that far - 7.4V is plenty for what I use.

- In addition, Li-Ions generally run higher than the specs: i.e. a 3.6V cell, when fully charged, will actually put out +/- 4.2V; if you do the math, 3 x 4.2V = 12.6V - way to high for me to risk using w/ CF.

- the third point is: 18650s are huge. 3 of them wouldn't fit in MHS, 1.5 sinktube or any other common hilt piece. You would have to find something larger.

:)

[xwingband]

What are you trying to run? For most cases a 7.4V li-ion pack will be fine. Also a 8.4V NiMH pack will get the higher voltage LEDs happy too.

[8lade]

I am going to run a 10w ledengin(the one with the 4 leds in one star)
going to run then 2 on the cf main output and 2 on the clash with the power extender+buckpack or 3 on the main and 1 for the clash.
Haven't tried it yet so I am unsure about the voltage requirements.
Any input on the project would be appreciated!
thanks guys!

[Malaki Skywalker]

The battery pack peeks at 12.6V... so I would NOT use it. :shock:

[8lade]

oook
I will go for the 7.4v one!
I have been testing this led and is quite bright I dare say!
it is a green one and I have pushed just one of its 4 leds to 3.2v at 1.5amps...it is not even getting hot!Obviously if I put all 4 one they will but I was thinking how much voltage and amperage could I push through a cf4.0 on 2 or 3 of the led cores connected in series...
Any suggestions?do you think would be possible?
thanks again for all the responses guys I hope I am not a pain in the @ss

[MoonDragn]

Run the leds 2 in parallel and 2 in series. Then you can use 6vs. The CF handles up to 1.5 Amps right? That means the 2 in parallel gets 750 ma each.

[Novastar]

CF could probably TECHNICALLY handle a bit more than 1.5A, but Erv put a cap on its output for a reason. So, yes Moon--CF will output a maximum of 1.5A, and so... you COULD send 1.5A to as many LEDs as you like... but the more you stack on, it "halves" the suggested battery mAh. If four LEDs... that cuts battery runtime to 1/4! D'oh!

Or, you could do what you were saying Moon and split the current for each pair, giving 750mA each LED and I believe that would only be 1/2 the battery runtime (two pairs @ 750mA each).

Either way... the more high current LEDs CF has to run... the quicker it'll be sucking the batteries down!

[Onli-Won Kanomi]

So do I understand correctly you couldnt use that 11v battery with a CF to run THIS?

http://www.ledsupply.com/07007-pb01-18-3.php

[Malaki Skywalker]

So do I understand correctly you couldnt use that 11v battery with a CF to run THIS?

http://www.ledsupply.com/07007-pb01-18-3.php

You can try it, but to me its to risky. :?

[Donnovan Sunrider]

What are opinions of this battery pack? It's one of the few I've seen that will fit in an MHS double-female tube that isn't super long.

http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=4308

There's also this one as a possibility.
http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=2714

[Ari-Jaq Xulden]

the second will not go in a mhs at all, the first one will but if your trying to get the whole pack in one mh section piece it would have to be 6 inches long. 134mm is about 5.5 inches.you would still have some room, but not much, for panel mount pieces like accent leds where battery is. they would probably help in keeping the pack from rolling around too a bit, but mesure twice cut once cut, it will be tight with space.

[Donnovan Sunrider]

Okay, I'm confuzzed now. I don't see why the either wouldn't fit.
The internal dia of an MHS piece is 1.24" wide.
Battery A is 1.2" wide (nice firm fit) and battery B is .866" wide (can roll around in there).

I know that if I were going with a 7" hilt it would be tight to fit it all lengthwise, but mine will be a 10" hilt piece for the base, so either should fit physically.

Are there other better suited locations to look for Li-Ion batteries? That site is one of the few that I've seen linked to, so that's where I've been looking.
Feel free to share links where experienced CF users have gotten good battery packs so us new folks can know better what our choices are. I want the best bang for my buck and space in the hilt. :D

[MoonDragn]

Both of them would fit in MHS as long as its not a choke piece or some of the narrow ribbed ones.

The first one is only 2.8 inches long and will fit in a MHS just fine at 1.2"

The second is 5 inches long and that would be half of your saber right there if you are using a 10" hilt.

Both of those are 7.4 volts though. I thought we were talking about 11.1v?

The one originally posted won't fit in anything unless your hilt is slightly wider than 1.5" Remember your 1.5" diameter is the Outside diameter of a sinktube, not inside. The inside is like 1.48" or something close.



Or, you could do what you were saying Moon and split the current for each pair, giving 750mA each LED and I believe that would only be 1/2 the battery runtime (two pairs @ 750mA each).

Either way... the more high current LEDs CF has to run... the quicker it'll be sucking the batteries down!

Well I was thinking of driving 1 pair with the CF and other pair with two 750 ma buckpucks or the power extender. (turned on by one fo the CF circuits)

That would be 3000 ma for all 4. Each one of those 18650s have 2400 mAh. So theoretically it would run 4800 mAH or about 1.5 hours.

[Donnovan Sunrider]

Both of those are 7.4 volts though. I thought we were talking about 11.1v?


I thought someone said that Li-Ion ran high, and that it came too close to risking the CF. The general consensus I've seen is that 7.4 is pretty good for most setups. Even Mad Hatter's Monster (http://forums.thecustomsabershop.com/showthread.php?t=6071) runs all of that on a 7.4 power supply (although a custom one).

[Jedi-Diah]

I asked Erv the same question regarding 3xLiIon cells and he said:

"I've tested the board at 12v and it worked, but the motion detection becomes noisy. Not recommended.
When full charged, 3 cells goes ABOVE 12 volts !
Erv'"

I'd like to try the red 10W LedEngin too but you probably need to go without sound for now.

[Novastar]

I want people to be clear on this, so... for everyone wondering about:

CF + "11.1v" battery pack = OK???? ? ?? ??? ?

Here ya go. Make sure you read it all so that you understand!!!!

It's true that "11.1v" packs are almost NEVER an actual, true to life 11.1v when they are fully charged--they are MORE. This is actually true of most any battery (non-rechargeable included!)... for examples:

X. Cell type -- ["LISTED/RATED", ACTUAL / REAL WORLD]

1. Alkaline -- "1.5v", 1.55v or even more in extreme cases
2. Ni-Mh -- "1.2v", 1.34v or even >
3. Li-Ion -- "3.6v", 4.2v or even 4.24v!!!

Now these are NOT perfect numbers, but the bloody POINT is: fully charged cells begin with OVER their rated (or AVERAGE) voltage.

The rated voltage is the AVERAGE voltage over the charge cycle.

Let me say this again:

A battery cell's rated voltage (by the manufacturer) is the AVERAGE voltage over the charge cycle... since the voltage drops as the battery is depleted of charge.

Ok... that being said...... 3 x 3.6v = 10.8 ... in the "rated" world...
But... if we look above... 3 x 4.2v = 12.6!!! ... in the real world.

Now that is an extreme case, but... STILL.

So... what is the answer you ask?!??! Can I use CF with 11.1v??!?!? Yes and no.

YES --- if you somehow REGULATE the voltage from the pack and essentially "cap it off" at a REAL 11v. With a voltage regulator, sure. Or some kind of diode (xener?? EDIT: probably RECTIFIER DIODES here, but I don't know). Whatever. If you don't allow more than 11v (eleven REAL volts, hehehhehe) through... you should be good!

NO --- if you decide to supercharge a bunch of cells, each brimming with amperage (and thus, voltage), topped off to the max, and then throw what you think is merely "11.1v". Then hook it up to CF. :rolleyes:

Finally, as you've heard from Erv himself... the board *CAN* work at even 12v... but then it's just the noise factor. And I doubt any of us know what the long-term effects would be. It might be somewhat akin to "pushing" an MR board to 6v or more. Do so at your own risk.

If this is all about using 11v because of the Rebel... there are better ways to use a "3-up" LED. It's called looking at serial vs. parallel... parallel vs. serial. :)

[Eandori]

I had an 11v pack "rated" hooked up to my CF for a short period of time. It would not work with the board so I quickly disconnected it and never tried again.

My pack was 9x 1.2v AA NiMH cells. Rating of 10.8v but on a full charge it got close to 13v

The only reason I even tried it is I assumed when Erv said 11.1v max he meant 11.1v rating on the cells. But no... Erv' meant an actual max of 11.1v. In this case, Erv' is a bit different then the industry standard, because when you buy cells for other consumer devices they tell you the max voltage for cell rating. Only electronic components usually go on ACTUAL cell voltage.

For example... if you buy an RC Car, it might say "7.2v accepted" but those packs will measure nearly 9v on a full charge.

If you buy a capacitor, it will tell you 10v max, they mean 10v is the max.

So... products = cell rating, components = actual voltage rating. Erv's spec for CF follows closer to component style. It's a good question that probably should be made very clear in Erv's manual.

Cheers,

[erv]

very well said & explained !
To be fully accurate : the problem is in the core voltage regulator. It accepts an absolute MAX RATINGS of 12V and regulates down to 3.3V. It's a big step down for a rail to rail regulator and when reaching 12V, it becomes noisy enough (on the electrical point of view) to get the motion sensor not "silent" enough. And it gets warmer too. While you might do various kinds of hack to solve that, it's just not a good idea to be so close to the specs and until now, I haven't found a good and cost effective rail to rail regulator that works on such a large voltage range
(to anyone : don't ask me why I'm not using a 7805 or something similar or I put your ass in my toaster hoven to see if it bakes CF boards better)

Erv'

[MoonDragn]

I wonder if you can use a buckpuck between the CF board and the 3 li-ion batteries.

It regulates current, but with a fixed load that means the voltage should stay constant.

[erv]

no you can't

[MoonDragn]

How about just a couple of resistors then? Take the voltage down to about 11V with the resistors and it should solve the problem.

[neophyl]

Resistors arent used to reduce voltage on their own, they are used to reduce current.

If the designer of a peice of circuitry says dont do it, its usually a good idea not to. Id listen to Erv if I were you.

[erv]

"nope you can't" is going to be a copyright sentence of mine now, I suppose ;)
neophil is right, you can't use a resistor.
Eventually, you could use a bunch of 1N4xxx diode in serie to get rid of the extra voltage... Then the nominal voltage will drop to about 10V.
Not the best idea but why not.

[MoonDragn]

Ahh I see what kind of circuit you have in there now. I can think of some other ways, but since it is a copyright thing, I'll keep it to myself.


Resistors arent used to reduce voltage on their own, they are used to reduce current.

If the designer of a peice of circuitry says dont do it, its usually a good idea not to. Id listen to Erv if I were you.

Guess you've never heard of a voltage divider. ;)

I like Erv's idea better though, rectifier diodes don't have the loading problems resistors would have.

[neophyl]

Guess you've never heard of a voltage divider. ;)

I like Erv's idea better though, rectifier diodes don't have the loading problems resistors would have.

As a matter of fact I have. I also know enough not to suggest using them for this application. You suggested using a single resistor, which isnt the same as a voltage divider network. I merely pointed out that wouldnt work on its own. There are lots of other options depending on size, efficiency, cost etc constraints that you have to work under.
If you already know about the problems of using a resistor in this capacity then why post potentially misleading information on a forum that can confuse those without the background in electronics some have ?

[xwingband]

Jeez, MoonDragn... I thought you said you were an EE?

I'll echo Neophyl why do you keep suggesting these silly things like a resistor to drop voltage?

[MoonDragn]

As a matter of fact I have. I also know enough not to suggest using them for this application. You suggested using a single resistor, which isnt the same as a voltage divider network. I merely pointed out that wouldnt work on its own. There are lots of other options depending on size, efficiency, cost etc constraints that you have to work under.
If you already know about the problems of using a resistor in this capacity then why post potentially misleading information on a forum that can confuse those without the background in electronics some have ?

Because I didn't know what Erv had packing under that CF. Just because I'm an EE doesn't mean I know whats in the black box. All I know is that theres a certain load condition that can't exceed a max voltage. A voltage divider can certainly work, and I didn't mean just one resistor, that was a typo there.

I had assumed the reason for the limitation was because the CF had some kind of current limit. Not a limitation on the supply voltage max of the regulator.

If you had noticed, all of my comments were posted in a form of a question, because I didn't know. I ask questions when I don't know something. Erv being the designer, knew more about his circuit, and was the perfect person to answer that question. This is a legitimate question, because some of us would like to run over 11 volts to the CF. Knowing how to get around its limitations is very helpful.

Thanks Erv.

[Novastar]

Ok, a typo it is. I will say these things though... that is the kind of thing that can be instantly edited (or edited anytime) on the TCSS threads. I actually am glad for this, as I like to fix my mistakes as quickly as I discover them for fear of others using the wrong info.

And on the other side of being a devil's advocate... I think we're all trying to discuss interesting ways of looking at >11v... and as long as none of us suggest things that are brainless, impossible and/or insulting, we should be good.

As it is, in my post before Eandori's... that is what I meant to say "rectifier diode" instead of the "xener" suggestion. Which is why I just suggested it with a "?"... since I wasn't totally sure.

In any case--it makes sense to me that if you have your cells... then PRIOR to *ANYTHING* getting to CF... you alter the cells current and voltage BEFORE they get to CF... it won't matter HOW you achieved it, as long as CF is essentially "oblivious" to the fact that the cells were once higher than what it likes.

I mean... you could take a 24v solution and hoover deluxe it down to 10v if you like. I don't know WHY anyone would do THAT to such an extreme, but... I'm assuming here that it could indeed be done.

Would this be wrong? Could you convert "high" voltage X to 10v prior to going to CF and CF would be "none the wiser", so-to-speak?

[MoonDragn]

I agree Novastar, I think the simplest is what Erv suggested. Three IN4001 rectifier diodes will drop the voltage by 2.1 v (I believe the voltage drop is about .7 v per diode). The IN4001s have a max current rating of 1A though so you might want to use higher rated types but the idea is the same.




Would this be wrong? Could you convert "high" voltage X to 10v prior to going to CF and CF would be "none the wiser", so-to-speak?

The above diode solution still wastes the extra current/voltage as heat. To be more efficient, a switching voltage regulator would have a higher efficiency especially for cases where the input voltage is much higher than the output voltage

Btw, just so you guys know. Even though I have a EE degree, my expertise is in Digital electronics, I suck at power systems.

[Novastar]

...Three IN4001 rectifier diodes will drop the voltage by 2.1v... [but the] diode solution still wastes the extra current/voltage as heat. To be more efficient, a switching voltage regulator would have a higher efficiency especially for cases where the input voltage is much higher than the output voltage.This I understand as well... that the diodes here would "burn off" the extra voltage as heat (much like a resistor's result)... and it'd be a bummer... but...

...if you REALLY wanted to use "11.1v" with CF--there ya go.

I also see where you're going with the whole idea of:

1. Ok, we have "11.1v", which is effectively a "true" 12v or 13v... too much for CF!!
2. Ok, I need to pull back on the reins here and not let so much current and voltage through!!! Whoa, Nelly!
3. Wait, hmm... I don't REALLY want to waste the extra V and A into heat--if I can possibly avoid it... but... can I?
4. Ok, I think I can do it. Sure, I COULD use rectifiers... but they'd still waste stuff. So... it's gonna go:

* BATTERIES (11.1v+) -->
* VOLTAGE & CURRENT GATE (in this case, you said "switching voltage regulator") -->
* CF ... and so now... CF is "none the wiser" that I ever began with > a true 11v... AND I'm going to benefit from the extra juice overall in the long run anyhow. Good stuff...

So... sweet! :) At least... I hope. That is... is this all just theory but in reality the solution is still flawed? Or... is it possible?

For all those who don't know... I have *NO* degree in EE or anything electronic-wise. I'm just a wise-guy with a sword or something... ;)

[erv]

basically an among switching mode regulator isn't a "bad" idea, it's just that you're going to waste power a little bit. However, since the regulation is just stepping a volt or so from the batt pack effeciency could run up to 96 or 98% so... yes, why not :-)