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What AWG Wires To Use
#1
"What wire size do you use for ESC, motor, LiPo batteries, signals...." I see this question all the time. 
So here is some info that hopefully answer this question for you.



First of all, there is no "overkill" when it comes to the size of a wire, you can use thicker wires than you need. 

A thicker wire means less resistance, and less resistance means less heat, better safety and higher efficiency. 

However thicker wires are heavier, so for weight critical application such as building a quadcopter, we should properly choose the AWG of electrical wires to achieve a good balance between current rating and weight.

Mini Quad components normally comes with wires soldered: for example motors, ESC, batteries.... If you want to extend the wires, you can simply match original wire AWG on these components. 

For example if your lipo came with 14AWG wires, you could use 14AWG wires for the XT60 pigtail.. And if motors were using 18AWG wires, but the ESC were using 20AWG, I would say it's best to match the larger wires, in this case, the 18AWG. 

Note that some manufacturers would deliberately use thinner wires so the weight looks better on paper.

For signal and data wires, 26AWG to 30AWG should do nicely. They don't really conduct a lot of current so light weight thin wires should be okay.

It's hard to say what the current rating is for a specific wire size, because it can depend on the conductivity of the material, length of the wire and many other factors, but here is a simple chart that you might find useful - https://oscarliang.com/wire-awg-chart-quadcopter-rc/

Beware that the length of the wire also matters, as it increases the resistance in the wire as it gets longer. Therefore if you are using a long wire you should be using a thicker wires. But generally speaking on a mini quad you should keep any wire as short as you possibly can.



Finally Study on Ohm's law it should answer some of your questions Smile

Don't be a LOS'er, be an FPV'er :) -- Blog - Facebook - Instagram - Twitter - Google Plus
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#2
Hey! That's a really good representation of Ohm's Law! R is one over VI !
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#3
i wish someone showed me this explanation of law during physics in elementary school Smile
it is soooo much clearer than description from books

as for the cables... signals can go basically on "whatever" what to watchout for are power cables especially battery = pdb as most current is flying through there...
All the best
Grzesiek (Grisha/ Greg)

Curently flyable: Nox 5, Nox 3, Minimalist 112, Scrap at the moment... nothing is flyable
Bench / in progres: fixing Nox 5, Nox 3, Minimalist 112, Scrap
thinking about building: 450

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#4
Good chart as a guide line, and the representation of Ohm's law is great.
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#5
Great post!
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#6
The insulation diameter is not very representative of wire AWG as you can see on the photo, especially for silicone wires.
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#7
Recently noticed that Core Electronics (http://www.core-electronics.com.au) has a pretty good range of colours in silicone insulated 30AWG cable at lengths and prices that are compelling.

Hobbyking have some but in general the colour range seems to be smaller - and their 26AWG is too "chunky" for doing much with on small frames.

Obviously largely relevant to Australian members but there's probably various Arduino/Hobbiest suppliers around the globe similar.
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#8
Silicone insulation is the best thing since sliced bread for any multirotor builder.

It doesn't melt or shrink back when you solder to the wire, it's easy to strip and the whole cable is so much more flexible.

There is one small disadvantage that should be considered though. As silicone insulation is quite soft, if any wire rests against a cut edge on your carbon fibre frame, you should reinforce that point with some heat shrink. If you don't, vibration will quickly cause the frame to cut through the silicone insulation and as carbon fibre is conductive, the results won't be pretty if you end up shorting power wires to your frame!

And even if you do reinforce with heat shrink, having any wire going over a sharp edge is a bad idea anyway and you should always try to avoid running cables in that way to start with.
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