The Fair Work Act 2009 is the principal federal legislation governing employment in Australia. It establishes the Fair Work Commission, which sets minimum wages and modern awards, and the National Employment Standards, a set of ten minimum conditions that apply to most employees.
Its protections apply regardless of visa status. Working holiday makers on a 417 are entitled to the same minimum pay, leave, and conditions as any other employee doing the same work, and contracts cannot lawfully strip those rights away.