Author Topic: Infinity DNA30 (Read 45432 times)

mamu · « **on:** January 16, 2014, 07:10:17 PM »

I made my rounds of forums earlier posting my new mod and wondered why I didn't get any replies here. It's not here, so must have done preview instead of post. duh-uh.

Infinity DNA30 has 2x LG 18650 30A 2500mAh batts in parallel for a total of 5000mAh 60A plus 2x 5A fuses in parallel wired to each batt.

74mm x 50mm x 22mm (2.91" x 1.97" x 0.87")

Maybe a bit top heavy with a Kayfun lol...

Breaktru · « **Reply #1 on:** January 16, 2014, 07:19:54 PM »

Well done mamu. Another masterpiece

jarjar2k3 · « **Reply #2 on:** January 16, 2014, 07:22:46 PM »

First post to thank you for your creativity.
It seems you have no limit.
I ordered my DNA30D yesterday, and I am starting to look around for electronic parts.
For sure I am going to follow your explanation on how you did such a marvellous thing.

mamu · « **Reply #3 on:** January 16, 2014, 07:34:24 PM »

Thanks breaktru and jarjar.

I kept wavering on which case I wanted to use for my 1st DNA30 and then finally chose this one this morning.

I love the teeny tiny up/down watts buttons. I nabbed those from a laser pointer pen and put a surface mounted tact switch behind them.

And dang if I didn't do the same thing at VF of previewing my thread instead of posting. gawd I must be getting senile lol.

rrtwister · « **Reply #4 on:** January 16, 2014, 07:45:42 PM »

Good choice of cases

very nice indeed.

kortt · « **Reply #5 on:** January 16, 2014, 08:04:11 PM »

Very nice looking mod mamu! It should really kick but with those LG's in it. Do you have on board charging or is there a battery door or something?

mamu · « **Reply #6 on:** January 16, 2014, 08:17:53 PM »

Thanks again guys!

There's a usb port on the bottom for internal charging.

methos · « **Reply #7 on:** January 16, 2014, 08:41:21 PM »

Luv that case mamu!!! Awesome work!!! Where did you get he case from?

Visus · « **Reply #8 on:** January 16, 2014, 10:20:33 PM »

We're so spoiled on the leading edge of it..

5000mah it still baffles me brain

redwolfe · « **Reply #9 on:** January 17, 2014, 01:38:31 AM »

Love it! Great size for the mah capacity, should get a few good days out of that.

CraigHB · « **Reply #10 on:** January 17, 2014, 03:51:14 AM »

Your mods have always looked so well refined, no change there. It's a beauty.

mamu · « **Reply #11 on:** January 17, 2014, 10:07:29 AM »

Thanks guys!

The case is/was a power bank that I had purchased a while back.

Quote from: CraigHB on January 17, 2014, 03:51:14 AM

Your mods have always looked so well refined, no change there. It's a beauty.

TY Craig! I'm a bit (strike that - a LOT) OCD with the aesthetics of my mods. Always have been - but I'm like that with everything. Drives hubby absolutely cuh-razy!

zeus17 · « **Reply #12 on:** January 17, 2014, 10:10:45 AM »

nice!!!!!!!!!!!

is it for sale?

wish we had things like that here in my country...errr.
everyone here is so wrapped up in mechs...

mamu · « **Reply #13 on:** January 17, 2014, 10:15:38 AM »

Quote from: zeus17 on January 17, 2014, 10:10:45 AM

is it for sale?

No.

You can make it happen though, zeus. Once you learn about safety and the foundation of modding, you're good to go with whatever you want to do with the build and choosing cases and parts.

zeus17 · « **Reply #14 on:** January 17, 2014, 10:44:53 AM »

Quote from: mamu on January 17, 2014, 10:15:38 AM

No.

You can make it happen though, zeus. Once you learn about safety and the foundation of modding, you're good to go with whatever you want to do with the build and choosing cases and parts.

yup i guess
hehehhehe

but again really cool mod..

jarjar2k3 · « **Reply #15 on:** January 20, 2014, 07:16:28 PM »

Hi mamu,

Was just wondering, do you use any kind of fuse in this set up?
If yes, which one are they?
Thanks,

mamu · « **Reply #16 on:** January 21, 2014, 03:17:27 AM »

I use these 2x in parallel on each batt for the DNA30:

Leaded: AGRF500-2 (5A hold, 9.4A trip, 2.5s trip time).

Surface mount: 1210L450SLWR (4.5A hold, 9A trip, 2s trip time).

jarjar2k3 · « **Reply #17 on:** January 21, 2014, 08:29:59 AM »

Quote from: mamu on January 21, 2014, 03:17:27 AM

I use these 2x in parallel on each batt for the DNA30:

Leaded: AGRF500-2 (5A hold, 9.4A trip, 2.5s trip time).

Surface mount: 1210L450SLWR (4.5A hold, 9A trip, 2s trip time).

Thank you Mamu, for taking the time to answer

c1truz · « **Reply #18 on:** January 21, 2014, 09:32:21 AM »

Awesome! Great looking too. You are pumping all these mods out faster than I could even imagine. I know ive seen at least 2 of yours and I haven't even got cases or boards for any of mine yet! I'm Jealous!!!

mamu · « **Reply #19 on:** January 21, 2014, 10:23:43 AM »

@jarjar2k3 - I should have mentioned this in my post, but the surface mounted fuses are teeny tiny, so I use tweezers to work with those to solder 2 together, then I mount the set on a piece of 1x3 veroboard where I removed the copper from the center portion.

I solder the fuses and the wires to the veroboard...

Then I slide shrink tube over the veroboard to cover the fuses and wires.

redwolfe · « **Reply #20 on:** January 21, 2014, 12:57:13 PM »

I need to get some of those SMD fuses soon. Working with the leaded ones has become a royal pain in the rear. Plus they take up much more space than is necessary.

Breaktru · « **Reply #21 on:** January 21, 2014, 01:31:54 PM »

I used the smd's on the last mod and was great. Didn't use the board, just piggybacked them. Nice and small.

redwolfe · « **Reply #22 on:** February 20, 2014, 12:00:09 PM »

Quote from: mamu on January 21, 2014, 03:17:27 AM

I use these 2x in parallel on each batt for the DNA30:

Leaded: AGRF500-2 (5A hold, 9.4A trip, 2.5s trip time).

Surface mount: 1210L450SLWR (4.5A hold, 9A trip, 2s trip time).

I want to put the SMD fuses on 1200mah 25C cells. Will 1 fuse on each cell be OK?

yogi · « **Reply #23 on:** February 20, 2014, 12:56:24 PM »

You can use (1) 6A on each cell. Not sure if you can find a 6A smd but I know they have 7A smd

redwolfe · « **Reply #24 on:** February 20, 2014, 01:33:10 PM »

Quote from: yogi on February 20, 2014, 12:56:24 PM

You can use (1) 6A on each cell. Not sure if you can find a 6A smd but I know they have 7A smd

That's 6A hold, correct? So the end result of 2 in parallel would be 12A which is within spec for the DNA30 board but I can't recall where I read on someone saying that even if the hold current didn't match or exceed the specs of the board the trip current should still exceed the specs of the board.

yogi · « **Reply #25 on:** February 20, 2014, 01:55:52 PM »

See: http://breaktru.com/smf/index.php/topic,723.25.html

CraigHB · « **Reply #26 on:** February 20, 2014, 02:14:47 PM »

Quote from: redwolfe on January 21, 2014, 12:57:13 PM

Working with the leaded ones has become a royal pain in the rear. Plus they take up much more space than is necessary.

It does seem rather odd that the SMD fuses offer similar performance to the leaded ones, but the body of the fuse itself is much smaller. It must be they put the best tech into the SMD ones and don't really develop the leaded ones. Generally, leaded components are becoming less and less available anymore. Best advice is to just get used to SMD parts, it's really limiting to avoid them. I went through a similar transition myself when SMD components started taking over the production scene, probably twenty years ago.

redwolfe · « **Reply #27 on:** February 20, 2014, 02:22:00 PM »

Quote from: CraigHB on February 20, 2014, 02:14:47 PM

It does seem rather odd that the SMD fuses offer similar performance to the leaded ones, but the body of the fuse itself is much smaller. It must be they put the best tech into the SMD ones and don't really develop the leaded ones. Generally, leaded components are becoming less and less available anymore. Best advice is to just get used to SMD parts, it's really limiting to avoid them. I went through a similar transition myself when SMD components started taking over the production scene, probably twenty years ago.

That's why I'm asking the question now. I want to get out of using leaded fuses and into the SMD ones. I was going to order the same fuses Mamu used in her Infinity mod like she mentioned above. Though they are higher priced and if I can save a little bit of money by using 4 3a fuses parallel I'll go that route. Even 7a SMD fuses are around $3 a pop and that's just a bit too much.

CraigHB · « **Reply #28 on:** February 20, 2014, 02:35:14 PM »

It can be hard to find the area on the web stie, but Littelfuse will send you free samples. They're pretty good about it and send the stuff pretty quick. Check out Littelfuse's line of "Lo Rho" fuses.

You can actually run pretty close to the trip current without issue. For example, two of the 3.5A Lo Rho fuses in parallel gives you a hold current of only 7A, but you get a trip current of 14A. That's high enough for a maximal load of 12A from the DNA30. With two in parallel, you get an insertion loss of only 5 mOhms which is awesomely low.

mamu · « **Reply #29 on:** February 20, 2014, 03:17:31 PM »

Quote from: redwolfe on February 20, 2014, 12:00:09 PM

I want to put the SMD fuses on 1200mah 25C cells. Will 1 fuse on each cell be OK?

I nixed using those fuses for the DNA30. Since I have a stash of the 3A smd fuses, I'm using 2x 3A smd fuses in parallel on each batt for dual batts in parallel which gives 6A per batt and 12A total.

Or you can use a single 7A smd fuse on each batt for dual batts in parallel for a total of 14A.

If you have just 1 batt, 2x 7A fuses in parallel would do for a total of 14A.

Littelfuse Surface Mount > LoRho Series

mamu · « **Reply #30 on:** February 20, 2014, 03:43:10 PM »

Quote from: CraigHB on February 20, 2014, 02:35:14 PM

...You can actually run pretty close to the trip current without issue. For example, two of the 3.5A Lo Rho fuses in parallel gives you a hold current of only 7A, but you get a trip current of 14A. That's high enough for a maximal load of 12A from the DNA30. With two in parallel, you get an insertion loss of only 5 mOhms which is awesomely low.

The max input current of the DNA30 is 12A, would you get inadvertent tripping from maybe internal or external heat or increased resistance if using 2x 3.5A fuses for 7A total hold current if pulling close to or at the max input current of 12A?

Above the hold current of 7A, but less than the trip current of 14A, the fuse partially opens. If the input current is say 10A, wouldn't there be increased resistance from the fuse partially opening above its hold current?

mamu · « **Reply #31 on:** February 20, 2014, 03:53:39 PM »

If you don't mind buying from alibaba.com, you can get Littelfuse's smd fuses a LOT cheaper than from buying at mouser or digikey.

This seller sells Littelfuse smd fuses as well as other electronic parts:
http://e-chipstock.en.alibaba.com/productgrouplist-213367419/PPTC_Resettable_Fuses.html

redwolfe · « **Reply #32 on:** February 20, 2014, 03:58:33 PM »

Thanks Mamu! I will definitely consider that option in the future. Right now I'm just compiling a list of parts for my prototypes. I will check out the seller on Alibaba.

CraigHB · « **Reply #33 on:** February 21, 2014, 01:49:46 PM »

Quote from: mamu on February 20, 2014, 03:43:10 PM

The max input current of the DNA30 is 12A, would you get inadvertent tripping from maybe internal or external heat or increased resistance if using 2x 3.5A fuses for 7A total hold current if pulling close to or at the max input current of 12A?

Above the hold current of 7A, but less than the trip current of 14A, the fuse partially opens. If the input current is say 10A, wouldn't there be increased resistance from the fuse partially opening above its hold current?

I've actually done a bit of bench testing with those particular fuses. You're right, external heat can cause the fuse to trip prematurely when loads are close to the trip current. However, I've only found that to be a problem when the fuse is mounted on a PCB next to components that generate a lot of heat. For a a fuse mounted in a free hanging manner on a small PCB or with wires soldered directly to the terminals, I don't think it's going to be an issue.

Even at the trip current, PTC fuses transition to a high resistance state very slowly, over a period of several minutes. The higher the fault current, the faster they trip. The fact that atomizers are powered only intermittently reduces the possibility of the fuse tripping prematurely. So, it's probably not going to be a problem with a 12A load and a 14A trip current.

One of the characteristics of a PTC fuse is the resistance doesn't go up until they reach the level of heat level that causes them to change state. They don't really ramp up in resistance as they approach the point of state change. So they'll maintain the range of inactive resistance below the trip current.

The reason hold currents are about half the trip current is to indicate a guaranteed continuous current level the fuse will not change state with the added influence of environmental heat, but again, atomizers are not powered continuously so the fuse is not influenced as much by heat buildup.

The benefit of running closer to the trip current is better protection, the fuse will trip faster when a fault current in encountered. So, there is some benefit there. Ideally, I'd go about halfway in between the two, but you can get away with pushing it a little closer for powering an atomizer, especially when the fuse is free hanging.

In any case, there's a Lo Rho fuse with an 8A trip which would provide a 16A trip with two in parallel. That one may be a better option if there's any concern about premature tripping.

deftones · « **Reply #34 on:** February 26, 2014, 02:06:12 PM »

Quote from: mamu on January 16, 2014, 07:10:17 PM

Infinity DNA30 has 2x LG 18650 30A 2500mAh batts in parallel for a total of 5000mAh 60A plus 2x 5A fuses in parallel wired to each batt.

Sorry if this sounds like a noob question, but it seems to me like a 20A fuse, isn't that too high for the DNA30?
I thought you used 2x3A?

mamu · « **Reply #35 on:** February 26, 2014, 03:59:16 PM »

Quote from: deftones on February 26, 2014, 02:06:12 PM

Sorry if this sounds like a noob question, but it seems to me like a 20A fuse, isn't that too high for the DNA30?
I thought you used 2x3A?

That's an oops as I misstated and should have proof read the OP before posting - I used 2x 5A fuses, 1 5A fuse per batt, not 2x 5A fuse per batt, for a total of 10A hold current.

Since then, I've been using 2x 3A smd fuses per batt for dual batts in parallel for a total of 12A hold current with the DNA30.

deftones · « **Reply #36 on:** February 27, 2014, 03:28:29 AM »

@ mamu

Thank you for clarifying that, makes more sense.

Maybe you'll have to back-proof read this OP on the other forums you may have posted it too, sorry, double duty.

@ CraigHB

Actually, I am concerned about premature tripping! I always wandered if there was a risk, and what's the margin we can use... If I use 2x6A and let's say I ultravape at 30W, should I rather go for 2x7A fuses instead?
Sorry, fuses confuses me.

Motanel05 · « **Reply #37 on:** February 27, 2014, 06:22:06 AM »

I have to confess something: to me you were the first moder which inspired me in everything I did afterwards. Esteem and appreciation for what you have done!

CraigHB · « **Reply #38 on:** February 27, 2014, 04:07:52 PM »

Quote from: deftones on February 27, 2014, 03:28:29 AM

Actually, I am concerned about premature tripping! I always wandered if there was a risk, and what's the margin we can use... If I use 2x6A and let's say I ultravape at 30W, should I rather go for 2x7A fuses instead?

If you're talking hold ratings, then you should be fine with 2x6A hold fuses. If that's the trip current, it's too close. You don't want to be on top of the trip current at any time. In any case, the hold current is the amount of current the fuse is guaranteed not to trip. Since there's less heating involved with the intermittent application of power to an atomizer, you can run above the hold current an amount, but I wouldn't go more than halfway between the trip and hold current rating.

The odd thing about PTC fuses is they state both a trip and a hold current which gets confusing. Other types of fuses don't use that specification. For those it's always the rated current which is equivalent to the hold current for a PTC fuse. For example a 20A slo-blo fuse will blow at a current somewhat higher than 20A, but they don't state the current at which they blow, only the current at which they are rated. The reason is there's a much wider difference between rated current and trip current for a PTC fuse. A 20A slo blo fuse will blow about 50% over the rated current, but a PTC fuse typically trips around double the hold current.

deftones · « **Reply #39 on:** February 27, 2014, 10:17:18 PM »

Yes, I was talking 6A hold and if I get you, 2 of them is the perfect match to the DNA30's 12A requirement, as it is "guaranteed not to trip" at that point but still protecting the board, right? The confusing part for me is that "trip margin" we shall use with the DNA, as we navigate between the 12A total hold for the down limit and the up limit of 24A trip for the up limit (is it?).
So... where is the "guarantee not to fry" up to?

I went for 2x6AH10AT.

Gotta admit I always have to read your posts twice, but thank you so much for the technical details, much appreciated!

Boonos · « **Reply #40 on:** March 15, 2014, 12:49:51 AM »

you're mods are awesome!

CraigHB · « **Reply #41 on:** March 15, 2014, 06:31:35 PM »

Quote from: deftones on February 27, 2014, 10:17:18 PM

So... where is the "guarantee not to fry" up to?

Wish I could tell you, but you'd have to sacrifice a DNA board to find out and I doubt anyone is willing to do that.

The problem when using a 12A hold with a 12A maximal load is that you don't reach the trip current until you're around double that and then the fuse doesn't actually trip quickly until currents are again much higher. A regular fast acting fuse does not have that problem since it will blow with currents about 50% over the rated current.

You can run a fuse with a lower hold rating and put maximal demand closer to the trip current, but that's a double edge sword. The closer maximal demand is to the trip current, the higher the likelyhood of a false trip.

From my own experience, I've found you can get away with using a fuse with maximal demand about halfway between the hold and trip currents, but that's no guarantee you'll never get a false trip. The up side is it will give you a fast trip with the currents you would actually see during a fault condition.

Fault currents are typically in the area of of 60 Amps using a good Li-Ion battery with low internal resistance. If the fuse trip rating is not a good amount below that, the fuse will not trip fast enough to protect the circuit.

deftones · « **Reply #42 on:** March 16, 2014, 08:46:42 PM »

That's exactly what I was talking about: navigate between false trip / not fast enough trip. Thanks for putting words and explanations on this, even if my brain hurts a little when I read your post again and again.

I guess I'm safe then, with my fuses between 6H and 10T. I could go halfway but why risking false trip if my DNA30 won't fry with some 10T?