1500V DC architecture reduces string count and can lower BOS cost in larger systems. 1000V DC still appears in smaller or older projects.
The product choice must follow the system voltage. Cable, connectors, fuses, breakers, SPDs and combiner boxes should be checked as one set.
1500V is common for commercial and utility projects
Longer strings mean fewer home runs and fewer combiner inputs. This can reduce material and installation work when the inverter and local code support 1500V.
1000V can still be suitable
Some residential, older or market-specific projects still use 1000V equipment. The important point is not to mix voltage ratings inside one DC protection package.