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Page 141

| fingers arranged in pairs so that they may surface well on both sides of the moving contact when the breaker is closed. Flat springs on the fingers permit the contacts to align themselves automatically on the wedge so that full current-carrying capacity may always be obtained. One or more pairs of fingers are used, depending upon the current capacity required. As a rule, the blade is also of large proportions to help carry off heat from the arcing tips. |

| Brush Contacts. |

| Brush contacts (Fig. 8-11) are usually used to insure good contacts where heavier currents are involved. The stationary contact consists of a solid copper stud, and the moving contact is made up of laminations. A wiping action takes place when the breaker is closing to ensure a good clean surface on which the laminations may make good contact. |

| Figure 8-11 Brush contacts: (A), (B), and (C) several types, and (D) wiping action. |

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