Introduction of distribution box series for LED display screen

Overview, the current on the zero line over the phase line current is a huge hidden danger, because there is no over-current protection on the zero line, there will be no protection, of course, there is no alarm prompt. Therefore, the zero line heating is very serious, a long time will directly cause a fire. Also seriously affect the life of transformers, cables my company for the LED display application market has launched a series of products QN-ZERO, 50KW-400KW ranging, stupid structure, do not have to debug the zero line current is too large mainly due to the third harmonic, the third harmonic is produced by switching power supply. The process from AC 220V TO DC 5V produces harmonics, mainly the 3rd harmonics. Next is the LED display screen has been a dynamic picture, three-phase will not balance, will also produce zero-line current. For a display screen with an area of more than 100m, the Engineering Party should advise party A to eliminate the zero-line current, the larger the screen, the more important it is that this cost can not be saved, can Use 1) scheme, namely Choose 4 + 1 national standard copper wire. Overall, for option 3) program cost than 2)40% higher cost, for more than 100 square display zero line current harm, so that we have to pay attention! Look at the fire display screen pictures are basically from the bottom of the horizontal ignition form, in fact, the horizontal main cable zero current is greater than phase wire 2 times and zero wire copper area is not correspondingly greater than phase wire copper area 2 times, zero wire overheating acts as a fuse. The solution to the problem: first, increase the area of zero line copper; Second, add zero line current eliminator. But both of them have the common fault of low power factor.