ETAP provides graphical underground raceway systems (UGS). Each ETAP project supports multiple views of the underground raceway systems. Each view is a conceptual cross-section of desired raceways and heat sources that are in the same vicinity. ETAP provides five types of calculations for cable derating analysis, namely, steady-state temperature calculation, uniform-ampacity cable ampacity calculation, uniform-temperature cable ampacity calculation, cable sizing, and transient temperature calculation. The steady-state temperature calculation is based on the IEC 60287 or the NEC accepted Neher-McGrath method.