6.45a, but theoretically it maxs out at 6a so therefore 20w at 3.1v is not possible.
It would need at least 3.3v to get 20w if it cuts off at 6a.
The "WeekEnder"
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6.45a, but theoretically it maxs out at 6a so therefore 20w at 3.1v is not possible.
It would need at least 3.3v to get 20w if it cuts off at 6a.
To calc what amps the dna is pulling you take the battery voltage divided by the output set wattage. So 20/3.1=6.45 watts
In RC I have puffed lipo's rather close to their limit from drawing too much current thru them, but I never had one go up because of current draw. All the lipo's I have seen go up have been from punctured cells....from crashes, mid air collisions, etc....we use to bring along a "lipo poker" for when we would puff up a lipo to were we didn't dare take it home. We would find a fire pit or concrete curb and puncture it on purpose.
A fuse should stop a dead short, without it you end up with a fire. If you are tightly enclosing the lipo in metal box, you now have a legitimate bom situation.
Even if the dna does malfunction, it's likely not going to draw enough current to hurt a battery like that.
I have used blade fuses and they work fine plus give you the ability to disconnect the power if you want or need to.
In RC I have puffed lipo's rather close to their limit from drawing too much current thru them, but I never had one go up because of current draw. All the lipo's I have seen go up have been from punctured cells....from crashes, mid air collisions, etc....we use to bring along a "lipo poker" for when we would puff up a lipo to were we didn't dare take it home. We would find a fire pit or concrete curb and puncture it on purpose.
A fuse should stop a dead short, without it you end up with a fire. If you are tightly enclosing the lipo in metal box, you now have a legitimate bom situation.
Even if the dna does malfunction, it's likely not going to draw enough current to hurt a battery like that.
I have used blade fuses and they work fine plus give you the ability to disconnect the power if you want or need to.
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That's amps not watts... Then add whatever internal loss in the DNA. My point was that the DNA can draw more than 6 amps from the battery if it's output limit is 6 amps..
That's amps not watts... Then add whatever internal loss in the DNA. My point was that the DNA can draw more than 6 amps from the battery if it's output limit is 6 amps..
Yeah yeah....Mr precise
....I think the DNA has a 95% or 96% efficiency rate.
I am going to try it with fuses I have, if it doesnt work I will fall back and regroup.
- The cutoff of a single fuse is 6.8a which would allow the 20w @ 3.1v scenario.
- The resistance is 0.016 to 0.027 so v-drop would be a nominal 0.06v (11w@3.8v) to 0.17v at the extreme (20w @ 3.2v).
- Plus its less than 1mm thick so its easy to incorporate.
- It will offer decent protection against a short, it is going to be a girly mod after all, so protection is a must. Its going to the GF (after I test it out for a week or two) so I definitely dont want any bombs!
Well, theoretically, the DNA will compensate for any v-drop on the input side, like this fuse, and it wont be seen on the output. I am hurting the efficiency of the Mod a tick, but not the output.
And I am raising the cutoff to an effective 3.2v instead of 3.1v.
So it doesn't look like I am getting a Tibs1 or Tibs2 anytime soon. I decided to repair my old DNA20 weekender, new up switch, new fire switch, put in a screen frame, and touch up any bad solder joints. PITA.
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So it doesn't look like I am getting a Tibs1 or Tibs2 anytime soon. I decided to repair my old DNA20 weekender, new up switch, new fire switch, put in a screen frame, and touch up any bad solder joints. PITA.
Impressive use of space, I like it....
BJ for some reason that looks like way to many wires
I have been using dinky servo wire for the switches, it makes that part easier.
And I will get my software installed at home so I can get working on the Tibs's
I have been using dinky servo wire for the switches, it makes that part easier.
And I will get my software installed at home so I can get working on the Tibs's
BJ for some reason that looks like way to many wires
I have been using dinky servo wire for the switches, it makes that part easier.
And I will get my software installed at home so I can get working on the Tibs's
I wonder why Evolv wants 24g on those switches.
What gauge is servo wire?
I have been thinking of using standard ribbon cable and putting my own Dupont connectors on them, and corresponding headers on the DNA.
I'm not sure what gauge they are, I have grundles of hobby king servo extensions in various lengths and gauges. The thin ones seem to work fine, just can't lolly gag around when soldering them
Ummmm, economical "for me", my machine shop guy has one.
Do you just need a hole or two? I could get him to tap a piece or two.
I need to verify that is what the aqua/origin threads are before I get to far into something. I can get a tap from china for $32 but I'm more hesitant than normal to order anything out of china.
I have a foot or so of ss 1" solid square bar that I was thinking would make a good a aqua/origin side by side base.
I have a foot or so of ss 1" solid square bar that I was thinking would make a good a aqua/origin side by side base.
I have both coming, if I get mine before you get your I will confirm the threading.
BJ for some reason that looks like way to many wires
I have been using dinky servo wire for the switches, it makes that part easier.
And I will get my software installed at home so I can get working on the Tibs's
Yep, two of each, one from the board and one from the switch, then I join them. PITA and I just cracked my screen and it is only showing the last two # and the W.
I am vaping my kayfun with the R41 at 17 watts and that's all that matters.Yep, two of each, one from the board and one from the switch, then I join them. PITA and I just cracked my screen and it is only showing the last two # and the W.
That sucks!!!! Hopefully the screen holds out, but one of mine did the same and a couple days later I lost the entire screen.
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