You can figure it out yourself like this:
Assume that you need to drop at least 1 Volt to get the power supply to startup.
R = 1V / A; where R= the resistance, and A is the current that you need (in Amps).
W = 1V x A; where W is the power dissipation (Watts).
Example; you need to plate 300 sq.in. at a current density of 2A per sq.ft.
300 sq.in. / 144 sq.in. = 2.08 sq.ft.
2.08 sq,ft. x 2A/sq.ft. = 4.16A
To drop 1V; R = 1V / 4.16A = 0.24 Ohms. W= 1V x 4.16A = 4.16 Watts.
As you can see, the resistance and Wattage changes with the current (Amps) you want. Its OK to drop more voltage, but it makes the required Wattage go up.
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