Cables are automatically routed and then sized by HST Software during site layout with the goal of minimizing total cable cost. Since different layouts are tested within each design iteration, the effect that equipment placement has on total cable cost is therefore evaluated and optimized within each design iteration. HST imposes the following constraints on cable routing:

1. Cables may only be routed in parallel with and perpendicular to racking structures. Therefore the azimuth of the racking structures dictates the directions in which cables may be routed.
2. All cables are single conductor construction.
3. DC String conductors are supported via the rack until they must travel between rows.
4. DC String conductors traveling between rows are installed in conduit.
5. Multiple DC string circuits may be installed within a single conduit.
6. DC Feeder and AC Feeder conductors are installed direct buried.
7. Multiple DC or AC Feeder circuits may be installed within the same trench but DC circuits may not share the same trench as AC circuits.
8. Spacing between DC or AC Feeder circuits is 7.5 inches.
9. No more than 12 DC Feeder circuits may be installed within the same trench.
10. Gen-Tie Lines are assumed to be overhead.