Hi to all experts forums... I can ask you the follow question or problem... I determine the magnetic field on one ferromagnetic piece by hall probe meter...The magnetization of this piece is longitudinal and the tipology of current is alternative current and set up the istrument on AC...The value that i read on display of the instrument in this situation is: I = 900 A Hmax (kA/m) about 3,8 In the same condition above i change the set up of instrument from AC to ACpk (peak AC). I read this value: I = 900 A Hpk (kA/m) about 13,3 if i readed in the first case the max value of H why i have two different result on H? In opinion sholud be the same H value but in not true...I wait, if possibe, the your answers..