I have to temp in existing 100 kw diesel generator. The load wires from the generator are paralleled 500mcm copper about 500' from the transfer switch.The existing 500 mcm are about 60' short of new location of transfer switch. I would like to use 350 al wire paralleled to run the last 60' on a temp basis.I would like to do this to save customer the expense of buying copper wire for a temp installation. I also want to do the correct installation even though it is going to be temp for possibly 9-12 months .Here is some misc info. The breaker at the generator is 400 breaker. The installation is residential.If you need any other info please let me know

Actually 500 mcm copper is rated 380 Amps.
Aluminum 350 mcm is rated 260 Amps, so extending with double wiring rates up to 520 Amps. No problem therefore!
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