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| line or equipment being worked upon cannot be energized accidentally. To differentiate them from air-break switches, they are called disconnects (Fig. 10-3). |

| 5. Air switches, equipped with arcing horns or arc suppressors, are known as air-break switches, and are capable of interrupting relatively small load currents (Fig. 10-6). |

| 6. Contacts, links, levers, and supporting structures must be maintained in a fashion similar to those of other circuit breaking devices. |

| 7. Potheads are disconnecting devices designed to connect or disconnect overhead conductors with conductors of underground cables (Fig. 10-13). They are usually de-energized before operating them, but under special conditions, may break only relatively small load currents. |

| STUDY QUESTIONS |

| 1. What is a switch? How many types are there? What are their functions? |

| 2. What is the difference between an air-break switch and a disconnect? |

| 3. When and how are disconnects connected in a circuit? What precautions should be used in operating a disconnect? |

| 4. What are arcing horns? What is their function? |

| 5. How many air-break switches have their interrupting capacity increased? |

| 6. What is the advantage of a load-break switch? |

| 7. What other types of disconnecting devices are there besides the air-break switch and disconnect? |

| 8. How are some of the larger air-break switches operated? What precautions should be taken before working on such a switch? |

| 9. Where and why are barriers sometimes used? |

| 10- What advantages do air-break switches have over circuit breakers? What are their disadvantages? |

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