Fuse derating according to the ambient temperature
This is defined by fuse manufacturer. Generally yes, but it depends on fuse type and sizing. For example, Mersen (Ferraz in the past) has
http://ep-us.mersen.com/fileadmin/catalog/Literature/Application-Guidelines/ADV-P-Application-Information-Temperature-De-Rating.pdf
where considered "normal" ambient temperature is 25 degrees centigrade.
When the fuse selection is associated with VSD or ATS, the max ambient temperature of VSD or ATS is already considered and so fuse selection is defined at this temperature.
http://ep-us.mersen.com/fileadmin/catalog/Literature/Application-Guidelines/ADV-P-Application-Information-Temperature-De-Rating.pdf
where considered "normal" ambient temperature is 25 degrees centigrade.
When the fuse selection is associated with VSD or ATS, the max ambient temperature of VSD or ATS is already considered and so fuse selection is defined at this temperature.
Released for: Schneider Electric USA
