12 AWG galvanized steel high tensile wire okay for running 12 volt 7 A DC?
The conductivity of metals varies about 10:1.
silver is the most conductive.
Copper is about 1/2 of silver
Tungsten is about 1/10 of silver.
Iron/steel ..... look it up, get the mils (diameter, or cross sectional area) and run Ohms Law.
Since you want DC, you need not be concerned with the time constant of the steel/iron atoms; just be aware that iron_derived wirings are SLOW to allow changes in current, because of the long delays in penetrating the atoms and causing the electron orbits to tilt in ways (that tilting does requires energy from the 7 Ampere current) that mutually align the orbits among atoms. That is what IRON does.
Thus you need substantial charge storage at the FAR END, at the LOAD end, of the wiring.
That simple steel &quot;wire&quot; will be many milliHenries of energy storage, and will be SLOW to allow changes.
To compensate for I * R voltage drop, you might set the 12 volts to 12.5 volts, if adjustable.
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This link provides a table (on the far right column) of Relative Permeabiility.
https://www.engineeringtoolbox.com/permeability-d_1923.html
The speed is 1/sqrt(Relative Permeability).
For #12 copper --- 1/8 inch or so --- expect about 0.1 second to settle to full voltage at the far end.
For pure iron, given the MUr --- Relative Permeability --- of 200,000, you should expect about 50 seconds. Thus the TURNON will be slow.
You are not using PURE IRON, so will be much faster.