Figure 9.10(b) shows the power vector diagram for the operation of the directional relay. ... There is also a normally closed feeder to a large electric utility system for the purpose of supplying any excess demand within the plant or to pick up the load if the ... This type of connection, however, creates an unusual problem with regard to protecting the system. ... back-feed from continuing, the secondary breaker is equipped with directional relays that will immediately trip the breaker as soonanbsp;...
|Title||:||Electrical Systems in Buildings|
|Author||:||S. David Hughes|
|Publisher||:||Brooks/Cole - 1988|