power line surge protector 1 Surge Protection for AC system 2 Can be replaced for the module not need power cut OBV4 series Surge ... suitable for TN-S, TN-C-S, TT, IT etc. power supply system of AC 50/60Hz, 380V, and used at ... the power system and give the indication signal, green means normal, red means abnormal.Model and Meaning:Main Technical Parameters:Demension: power line ...