wire size vs current
Here's a general guide
Copper wire resistance table
Feet/Ohm Ohms/100ft Ampacity* mm^2 Meters/Ohm Ohms/100M
AWG
10 490.2 .204 30 2.588 149.5 .669
12 308.7 .324 20 2.053 94.1 1.06
14 193.8 .516 15 1.628 59.1 1.69
16 122.3 .818 10 1.291 37.3 2.68
18 76.8 1.30 5 1.024 23.4 4.27
20 48.1 2.08 3.3 0.812 14.7 6.82
22 30.3 3.30 2.1 0.644 9.24 10.8
24 19.1 5.24 1.3 0.511 5.82 17.2
26 12.0 8.32 0.8 0.405 3.66 27.3
28 7.55 13.2 0.5 0.321 2.30 43.4
I would use less current (~ 15% less) for AWG 20 -->AWG 28
Hope this helps