At present a lot of impact on power grid entities electromagnetic interference of industrial control equipment, is widely used. This part of the equipment including inverter, inverter welding machine, high frequency heating equipment in familiar devices, they are all typical electromagnetic interference sources. If in the electric control system, according to these measures to prevent electromagnetic interference sources such as shielding, grounding processing does not reach the designated position, are highly vulnerable to the interference of other electrical equipment, cannot normal operation happened even failure phenomenon is very strange
Last October, the author once went to a unit overhaul electric control cabinet. The unit one in electrical control cabinet of dc 24 v relay operation system, in the so-called often occurs after transforming slow action, and bad, and so on and so forth, back and forth, and used to provide power AC220V/DC24V relay switch power supply is also often burned fault! When open the control cabinet, I glance at finding out the cause that the crux of the problem - the unit in order to save money, in the control cabinet shoehorned into the two 5.5 KW inverter, more important is for the two inverter do not make any electromagnetic interference filter action!
To sum up, when the electronic control system electrical equipment operation happened repeatedly switch back and forth, the abnormal situation such as action, you can reference cited three possibilities of induced failure phenomenon, a serious overhaul, and take corresponding measures to improvement.