[en] ac losses have been measured in several samples of the Nb/sub 3/Sn compacted cable conductor to be used in the coil designed by Westinghouse for the Large Coil Program. Losses were measured in the individual strands, in compacted cables made of uninsulated strands, and in compacted cables made of strands which were insulated before cabling and reaction. For ramp rates in the neighborhood of 0.1 T/sec. the losses are dominated by coupling between strands in the uninsulated cable. The insulation reduces the losses by more than an order of magnitude to a level that appears to be acceptable for the test conditions of the Large Coil Program. Bend tests have been performed and the effects on the losses in the insulated conductor determined. This magnet is for fusion applications. 5 refs