turns comparison

[lucifer]

Some years ago, I got a Wire Table chart, and it had varsious things on it, I guess for importance. One of two things that struck me was, one was OHMS per 1,000 feet, at 20 degrees Centigrade.

The second was, CURRENT CARRYING CAPACITY at 7000 C.M. per Amp. So I am going to ask this question. Is one, or both of these, or just one of these of what I call of PRIMARY IMPORTANCE??? Now it also has an area, describing TURNS per Linear Inch (25.4 MM). It also rates the wire, as A.W.G. with (B&S) in brackets.

Is the OHMS more important then Current???

Any explanations that I should know about anything as far as winding the coil???
Melbeta

Hi,
I think both should be considered when dealing with higher currents.
Ohms per foot or meter is simply the wire resistance and it's usually specified at 20 degrees C. At higher temperatures resistance gets slightly higher. The resistance is directly related to the maximum current through the wire (Ohm's law).
Current carrying capacity or ampacity is the maximum current the wire can carry without exceeding its temperature rating. Higher currents cause the wire to get hot and heating it above certain point is likely to damage its insulation and destroy your coil as well as cause other problems.

[Carl-NC]

In metal detectors ampacity is not important, you will never reach that point. Resistance is very important, for different reasons in VLF & PI designs.