Silicone insulated wire has a higher temperature rating (usually like 200 degrees C), and consequently it can handle relatively higher currents than a comparable wire with normal (pvc plastic) insulation – of course this doesn’t say anything about what the wire is touching and if it can handle the higher temperature, but anyway.
You came here to answer the question “I have some silicone wire, how much current can it handle”, here’s a rough rule of thumb
Take the cross sectional area in mm2, multiply it by 25 and that’s a reasonable current capacity in Amps for SILICONE wire.
Example:
Cross sectional area: 0.5mm2
Multiply by 25: 12.5
So that’s about 12.5 Amps, let’s call it 12.
I know the AWG but not the cross section:
Wikipedia has a table which includes the area of AWG wire sizes
Where does this come from?
Here is a reference to this approximation.
The “rule of thumb” is usually expressed in “circular mils per amp”. A circular mil is one of those weirdo American units, in this case the circular mils of a wire are equal to the square of the diameter of the wire measured in “mils” (1/1000 of an inch).
If you wanted to verify our “mm2 * 25” rule-of-thumb against the circular mils rule-of-thumb, it’s pretty easy to do so, let’s again say our wire is 0.5mm2
First calculate the radius, remember area is PI*R2 , so we divide by PI and take the square root to get R = 0.3989, and the diameter is double that, so D = 0.7978mm
Now there are about 39 mils in a millimeter, so multiply that by 39 and we get D=31.1142mils
Circular mils are the square of the diameter, so that’s CM = 31.11422 = 968.0934
And the fairly arbitrary divisor is 80 circular mils per amp, so 968.0934 / 80 = 12.1011 AMPS
Convenient quick lookup for check thanks to Wikipedia’s AWG Table:
Wikipedia’s AWG table includes a “kcmil” column, that’s kilo-circular-mils, this makes it easy for our rule-of-thumb is you know AWG.
So for example if we look up 20AWG in that table, you’ll find it has 1.02 kcmil, so we can calculate 1.02*1000/80 = 12.75 AMP
Yes, the numbers we get are different. Remember this is all approximation, rule of thumb, exact wires differ in cross sectional areas (esp stranded vs solid), and some of the numbers are completely arbitrary (amps per cmil) and just chosen as “that seems about right”.