The dc grounding method

A independent grounding:as discussed above the needs of the grounding part,each independently set up their own grounding system,the grounding method,called independent grounding.It has the advantage of not cause mutual interference between each system,it is especially important for communication system.But the network is liable to be struck by lightning bad,so in addition to is in danger of explosion proof requirements must adopt independent way of lightning protection of the environment,generally do not adopt the way of independent grounding.This independent grounding in the 60 s and seventy s before use is more,now replaced by common ground.Second,common ground:also called unified wholesalemotor.blogspot.com grounding.

It is unified all the need for grounding system receives a grounding device,or the original

grounding device each system through underground or on the ground with a metal conductor

connected,make them ac electric motorsbecome smooth electrical grounding network,between the grounding method for common ground.Common grounding is currently the most widely used.Three,one-point earthing:each system grounding line connects to ground strap the same point or the same metal plane,one-point earthing method can solve the potential ac alternators 220v problems such as ground wire of each system,so can reduce the degree of interference between each system,especially the electric motors price 50 hz power frequency signal to eliminate interference on the system basically,so a little grounding method is widely used in engineering.A little grounding eliminates common impedance coupling and low frequency interference caused by ground loop.Can work well in more than 1 MHZ and frequency,when the size of the whole system is small (maximum size less than 20,l/l for jamming signal wavelength) can be applied to the 10 MHZ.