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ArcticMyst Security by Avery

About Cable diameter

SOG

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HI Guys, this might sounds like a newbie questions, but after I look at some of the builds you guys do in here, I found the Cable Diameter seems a little ... "small" or not thick enough, especially for a cable that will pass 1A or over's electronic currents? I saw some said their build can go over 1A in current. it's electronic currents, right?

But then if 1A of electronic currents... I don't understand how the cables from the battery to the driver, and form the driver to the diode is so ... small in diameter? it looks like it can't withstand it, or it will just make alot of heat, or just burn out? I am sure copper quality makes a different, but most cables I saw still look somewhat "thin" or small in diameter compare to its' currents.

Please let me know what you guys think? :) Um... I know Voltage also come into play too... but for 1A or 1.8A... um...
 





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We generally use high-quality wire which is incredibly heat resistant and made up of many strands of copper interwoven. I think that answers your question... but lemme know if it doesn't?
 

SOG

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We generally use high-quality wire which is incredibly heat resistant and made up of many strands of copper interwoven. I think that answers your question... but lemme know if it doesn't?

Um... actually I am sure you guys using high quality wires, otherwise I am pretty sure they would be so hot and burn the plastic around it when you run has such high current through it.

but I don't understand why not using a thicker, bigger in diameter wire to reduce the heat and also to save the energy? have special reasons of doing that? or just to save spaces?
 
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Yeah, it's entirely for flexibility and to save space. The wire that we generally use is silicon-insulated and it's somewhere in the 26AWG range.
 
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The cable can not be too big (fat) because the small space, and for this reason must also be very flexible "as stated by Wolfman29", also to make the connections (welds) with the driver and the diode without problems, must be thin and flexible.

Anyway the cable used is sufficient for the power consumed by the diode, and not heated by lack of diameter, also because the distance is short to warm up for lack of diameter.

The cable insulation must be resistant to heat, mostly because the heat dissipated by the driver, but mainly by the diode, (also has to withstand the heat when soldering to the diode and driver), but not because it is heated by the power consumption.
 

SOG

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I see... that explain alot, because I also notice most o the soldering point on the driver PCB are quite small... thanks for explaining :)
 
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Look at the tiny wire inside a 1 Amp fuse. Now look at the stranded wire we use.
Quite a difference. As for resistive losses (I^2xR) , the wires are hardly an inch long.
HMike
 
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Here's a guideline. 28 gauge will carry 1A just fine, and most people use 26, 24, or bigger.

Current capacity has nothing to do with the number of strands.
 

SOG

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Look at the tiny wire inside a 1 Amp fuse. Now look at the stranded wire we use.
Quite a difference. As for resistive losses (I^2xR) , the wires are hardly an inch long.
HMike

um... I think 1A fuses have sliver around it? or I mean it's different materials?


But thanks guys, now I see why using smaller wires... I can see space for the PCB and Diode being a matter and concerns. but still I think bigger in diameter is better :) but then two thoughts comes to mind,

1. if the small wires works, why use big ones...

2. :evil: It's not the size that matters, but how you use it :evil:
 
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My girl is always telling me I got the biggest wire she has ever seen :bowdown:
 
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The number of strands can affect current carrying capacity as electron flow becomes a surface (skin) effect for higher frequencies (alternating current), where to maintain current ratings more strands are needed to increase the surface area

ONLY if the strands are electrically insulated from each other. The vast majority of stranded wire does not have this characteristic.
 
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The primary benefit of multi-stranded wire is flexibility, not an improvement in current capacity.

And SOG.. In a lot of builds. space is cramped, and there is a lot of twisting and cramming required to assemble them. Larger wire isn't as flexible and would likely never survive assembly in a lot of builds. 2.2A @ 4.2V is over 9W.. very few builds will draw anything even near that, and the ones that do (assuming battery side.. diode side won't have anywhere near that current typically) are constructed in much larger hosts that don't have the size constraints to require small super flexible wire.
 
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My girl is always telling me I got the biggest wire she has ever seen :bowdown:


Thats only because she hasn't seen mine yet.
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