What load can you put on 3- 2x10x17' long?

The load capacity of three 2x10x17' beams depends on several factors, including the type of wood, the spacing between beams, and the load's application (live load vs. dead load). Generally, for typical softwoods, three 2x10 beams can support a combined load of approximately 1,500 to 2,000 pounds when spaced properly and used for floor support. However, it's essential to consult engineering tables or a structural engineer to determine the exact load capacity based on specific conditions and building codes.