Definition: | the reaches of the measuring elements of non-unit protection, generally distance protection, in a power system
NOTE – These non-unit protections, generally distance protection, often have two, three or even more zones available. These are usually arranged such that the shortest zone corresponds to an impedance slightly smaller than the impedance of the protected section, and is normally instantaneous in operation. Zones with longer reach settings are normally time-delayed to obtain selectivity.
|