What type and size of conduit is used between the 70-kilowatt emergency generator and the automatic transfer switch?

For a 70-kilowatt emergency generator, the appropriate size of the conductors and conduit must take into account the electrical load, the ampacity of the conductors, and the physical installation requirements. The selection of a 1 1/4" conduit with 1 AWG conductors is suitable for this application as it allows for sufficient space for the conductors while also accommodating any potential future expansions or additional conductors if needed.

The 1 AWG conductors are capable of handling the necessary current load from the generator to the automatic transfer switch, ensuring that the system operates effectively and safely. Additionally, the slightly larger conduit size aids in heat dissipation and makes the installation less crowded, which is often a consideration in electrical installations.

This combination adheres to the guidelines set forth in the National Electrical Code (NEC), taking into account the fill capacity of conduits and ensuring that there is enough space for the cables without exceeding the maximum fill ratio. This choice of conduit and conductor size supports both electrical safety and efficiency.