APPLICATION HY1 series surge protective device (SPD) /Surge Protector is suitable for AC 50/60 Hz. 380V and the following electric power system, such as TT, IT, TN-S, TN-C and TN-C-S for protecting electric net shocked by the thunder or over voltage. Technical parameters Maximum continuous operating voltage : Uc~ 140 275 320 385 420 550V Test grade : Voltage protect level: Up 0.8 1.2 1.5 1.8 2.0 2.5 kV Maximum discharge current : (8/20) Imax 10 40 60kA Nominal discharge current: (8/20) In 5 15 20 30kA