dwh
Tail-End Charlie
2 AWG wire is good for 450A max for 48" runs
Sweet. So with a 500a fuse, the wire will protect the fuse.
But actually, that chart says "Total System Length" at the very top. So a 48" total system length would be a 24" run. For a run of 48", the total system length would be 96" and according to that chart, #2 would be good for 200 amps.
But technically, my question wasn't, "What's it good for?" - my question was, "What's it rated at?"
According to the National Electrical Code, Table 310.15(B)(16), 2 gauge AWG is rated between 95 and 130 amps depending on insulation type and temperature.
Anyone can make up their own chart, and many do. Those are NOT official wire ratings.
If I were using welding cable and wanted to ignore the NEC ratings, I'd go with welding ratings. Here's a chart from Lincoln:
http://www.lincolnelectric.com/en-u...ges/selecting-proper-size-welding-cables.aspx
[Note that duty cycle plays a part in how welding cable is rated.]
Personally, if I wanted to serve a load protected by a 450a or 500a fuse, I'd go with 2/0 (two-ought) welding cable, not #2. Unless I expected to have a 100% duty cycle, in which case I'd bump it up to 3/0.