1. 7203SYZQE Substitution Conclusion Substitution is feasible, but requires derating and attention to mounting compatibility. Compared to the original part 5649AB, the key differences of the 7203SYZQE are reduced current and voltage ratings (from 6A AC/125V AC to 5A AC/120V AC), shorter electrical life (from 50,000 cycles to 40,000 cycles), and a slightly smaller panel cutout diameter (6.50mm vs. 6.35mm). If the original circuit operates close to 6A, direct replacement carries an overload risk; the actual load must be confirmed to be ≤5A. The reduced life cycle may slightly affect long-term reliability in high‑frequency switching applications. The minor dimensional difference is generally compatible but should be verified. Other key characteristics—such as circuit configuration, number of positions, sealing process, and terminal type—remain identical, enabling a functionally equivalent substitution.