click below
click below
Normal Size Small Size show me how
Self-Test 1 Q&A 4-5
Self-Test Questions Volume 1
Question | Answer |
---|---|
Name three types of distribution panels. | Lighting and appliance panels, power panels, and feeder panels. |
What is a lighting and appliance panel? | A panel-board that has more than 10 percent of its over-current devices protecting lighting and appliance branch circuits. |
What is the purpose of a power panel-board? | To provide power for the operation of electrical equipment. Most of the branch circuits from the power panel are 240 or 480 volts. |
What type of panel-board is set up to furnish power to other panel-boards? | Feeder panel-board. |
Why would a panel-board furnish power to other panel-boards? | This allows branch circuits where they are most useful, with an overall savings in material. |
What information must appear on a panel-board? | The voltage, current rating, number of phases, and the manufacturer's name or trademark. |
What are the grounding requirements for panel-boards where wiring is done with nonmetallic cable? | A terminal bar must be provided for attachment of feeder and branch circuit equipment-grounding conductors. This terminal bar must also be bonded to the cabinet. |
How is the high-voltage conductor of a four-wire, delta-connected system with the midpoint of 1-phase grounded identified? | It should have an orange outer finish or be tagged clearly. |
On what is the capacity of a fuse panel based? | On the amperage rating of the panel's bus bars. |
What is a dead front fuse panel? | A panel that has no live parts exposed when the door is open. The cover must be removed to gain access to the interior parts. |
What are three types of fuses used in fuse panels? | Plug fuse, cartridge fuse, and knife-blade fuse. |
What is the main advantage of a circuit breaker panel over a fuse panel? | When an overload occurs and trips the circuit breaker, the breaker can be reset to restore the circuit without having to remove and replace it. |
What is an added convenience of a circuit breaker panel? | An added convenience of the circuit breaker is that it can be a switch to manually disconnect a circuit from its power sources. |