The current carrying capacity tests of fuses are performed at 25˚C and will be affected by changes in ambient temperature. At higher ambient temperatures, a fuse will respond faster to a given overcurrent condition. Conversely, at lower ambient temperatures, a fuse will respond slower to a given overcurrent condition. In addition, the temperature of the fuse increases as the current carried by the fuse approaches or exceeds the rating of the fuse. Different fuses will have different re-rating curves based on the construction. Some fuses have minimal changes in fuse rating over a wide temperature range, whereas others have significant changes over a given temperature range.