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Page 212

| Figure 11-13 Open-type fuse cut-out: (A) Construction details. |

| Three-Shot Fuses.. |

| At remote locations or under certain special circumstances, it may be desirable to have a circuit back automatically after a temporary fault. If the line is fuse-protected, a three-shot fuse holder is used (Fig. 11-15 on page 214). Three fuses per pole or phase are mounted in parallel, but only the first fuse is connected to the load. When a fault or overload occurs, the first fuse will blow. As it swings open (in the drop-out type of fuse holders), it causes a latch to operate that places the second fuse in service. If this blows, a similar action places a third fuse in service. If the third fuse blows, the circuit remains disconnected. While all three fuses are similar as a rule, on special occasions |

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