I've got a 120KW water heater with a nameplate load of 144 amps. The elements are individually fused at 60 amps. The main feed is 2/0 THHN fused at 200 amps. I'm wondering if the 200 amp fusing is code compliant based on the nameplate load and the 2/0 conductors. Because the 2/0s are rated for 175 amps and the elements are individually fused, I think the installation is fine. However, is it code compliant?