the integral of the square of the current over a given time interval:
NOTE 1 – The pre-arcing I2t is the I2t integral extended over the pre-arcing time of the fuse.
NOTE 2 – The operating I2t is the I2t integral extended over the operating time of the fuse.
NOTE 3 – The energy in joules liberated in one ohm of resistance in a circuit protected by a fuse is equal to the value of the operating I2t expressed in A2 • s.
|