There is a calculator application available here:
http://www.ultracad.com/calc.htm
Scroll down to Wiregage.exe.

Also see: http://www.pcdmag.com/resources/equations/
-Denis

At 11:38 AM 1/4/2002 -0600, you wrote:
>In the August 1997 issue of Printed Circuit Design there was a Designer's
>Viewpoint column that had a conversion chart for finished trace widths to
>standard wire gauges.  It has copper weights of 1/2, 1, and 2oz related to
>AWG ratings ranging from #39 down to #10.  For instance, to get the
>equivalent of AWG #10 in a 2oz non plated trace, it must be 0.472429" wide,
>for a plated trace, 0.344745".  It also gives the resistance/inch for 20, 50
>and 75 degrees celcius.
>It doesn't give current carrying capability, but you can usually get current
>ratings of AWG wires.  Do you have to do 80A all in one trace?  Can you run
>some wires in parallel with the trace on the board?
>
>-----Original Message-----
>From: Shannon Stutzman [mailto:[log in to unmask]]
>Sent: January 4, 2002 11:01 AM
>To: [log in to unmask]
>Subject: [TN] Copper
>
>
>Hello everyone;
>
>I am looking for a chart or an equation that will allow me to find the
>copper thickness needed in relation to current.  I have the chart that is
>given by IPC but this chart dose not give current ranges or copper
>thicknesses high enough for my application.  I need to how thick of copper
>to use for 80 amps and what the minimum trace width that can be used.  If
>any of you have any information on this I would appreciate it.
>
>Thank you.
>
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