The Electricians Tool Pouch 2011 - Tool Box. CU to AL THHN copper wire to aluminum conversion. Selectable: 75, 90 deg. C conductor insulation temperature rating, conduit type, and three-phrase four-wire with ground wire configurations. Calculates: Conduit size for copper wire. Calculates: Allowable amperage. Calculates: Conduit and wire sizes for equivalent aluminum wire.