symmetrical and unsymmetrical fault


~ there are two types of fault

1) symmetrical 

2) unsymmetrical


~ in a symmetrical fault, the value of the fault current of the three phase is the same and there is a phase difference of 120* between each other.

~ LLL type fault are usually symmetrical type.

~ in an value of the fault current is not the same in all the three phases, not is there a phase difference.

~ LG,LL,OR LLG type fault are of unlimited types.

~ most fault in the power system are of the unlimited type.  


     difference between abnormality and fault

~ next we discussed the abnormal operation and fault of the power system.

~ from this it will be know that fault cause is while abnormality is the result.

~ because the first fault occurs and a lot of cuts flow due to the fault.

~ this cause the abnormal condition as shown above.

~ however, not all abnormal conditions are caused by fault alone for example. overloading of  equipment.