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| tions. The upper and lower portions are assumed to be identical in electrical characteristics. Fault locations, indicated by an x, are identified by a circled number. Alongside the number appear the maximum (on the left) and the minimum (on the right) fault currents; all currents are in amperes at 23 kV. The current distributions and directions for each fault location are also specified. For example, the current in line AB for fault number 2 is 1000 amperes maximum and 750 amperes minimum; there is no contribution of fault current from the 7.6-kV distribution system. |

| Where both overcurrent and directional-overcurrent relays (or elements in the relays) exist, the overcurrent setting is made high enough so that the directional element will normally close first, except for faults at or very near the breaker. In the latter case, the overcurrent relay will operate to open the breaker almost immediately. This, however, is a simplified explanation. |

| Figure 14-5 (A) Typical system and zones of protection. |

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