The maximum current, in amperes, that a conductor can carry continuously under the conditions of use without exceeding its temperature rating
A conductor can safely carry much higher current for short periods of time. A continuous current of a given magnitude will cause more heat to build up in a conductor than the same amount of current imposed for a short period of time.
•The temperature rating that is important here is the temperature rating of the conductors insulation, not the temperature that would damage the metal conductor material itself. A temperature that would damage or destroy the insulation could result in short circuits. Ground faults. arcing. and possibly fire. not to mention damage to other electrical equipment to which the conductor is connected such as switches, overcurrent devices, appliances, or luminaires.