Electrodynamic forces in case of non-simultaneous short-circuit in three phase A.C. circuit

which acts on three phase carrying-current condutor in horizontal arrange

was calculated in this paper. It shows that

in the severest condition

the direction of maximum electro-dynamic forces

which acts on left

middle and right conductor

severally is leftward

leftward and rightward

and the maximum of them severally is 1.2

1.4andl.4 times of the maximum in case of three phase simultaneous short-circuit. From this

it is proposed the peak withstand current of high voltage switchgear should be equal to peak current in case of non-simultaneo-usshort-circuit in three phase A.C. circuit.