Frames: Sophisticated design software and over 75 years of experience ensure that the generator frame is made with strength and support where needed instead of just adding useless size and weight. Stator frames are welded with heavy rings and bar steel. The frame is reinforced with welding plates between bars or with a heavy wrapper. Heavy gauge steel is formed and fasted to the frame to provide an ample airflow path. The endrings are precisely machined to support the bearing brackets.

Cores: Stator cores are built from high-grade electrical steel laminations. Each lamination is core plated on both sides to minimize core loss and heating. Slots in the cores are skewed to minimize harmonic voltages.

Form-wound windings: Because of the high voltages they incur and their importance to generator performance and life, the stator coils are the heart of a generator. The equipment Kato Engineering uses to make these coils is, indisputably, the most modern, most precise and best in the world. Insulating tapes are precisely layered to ensure maximum insulation properties and optimum fit in the coil slot, eliminating discharges that would shorten the generator’s operating life. In the stator, coil end windings are braced and supported with surge ropes to withstand short-circuit fault conditions. 

Entire stator assemblies are immersed into liquid thermosetting epoxy resin insulation and vacuum-pressure impregnated. The vacuum exhausts air, moisture and other vapors from the windings and permits complete penetration of the epoxy resins, filling voids and creating a rigid mass with optimum dielectric strength.

Random-wound windings: Random windings are used for selected applications under 1000 volts and for high frequency generators. The windings are made with the highest quality round copper wire, which has a heavy film coating rated at 200° C.