Services Questions and Answers |
Latest Version | 2024/2025 | Correct &
Verified
What is the purpose of performing load calculations for feeders and services?
✔✔ To ensure electrical systems are safe and comply with code requirements.
Why is it important to consider demand factors in load calculations?
✔✔ To account for the likelihood that not all connected loads will operate simultaneously.
What is the definition of a feeder in electrical systems?
✔✔ A conductor or group of conductors that carry power from the service equipment to branch
circuits.
What is a service load calculation?
✔✔ A calculation to determine the total electrical load supplied by the utility to a building or
structure.
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,Why must continuous loads be multiplied by 125% during calculations?
✔✔ To account for the potential of continuous operation and ensure proper conductor sizing.
What does the term "general lighting load" refer to?
✔✔ The load required to power the lighting fixtures of a building.
What is the purpose of a neutral conductor in a feeder system?
✔✔ To carry the unbalanced current in a multi-phase or split-phase system.
Why is it important to use the NEC when performing load calculations?
✔✔ To ensure compliance with electrical codes and safety standards.
What is a demand factor, and how does it affect load calculations?
✔✔ A percentage applied to connected loads to determine the actual expected load.
Why are small appliance branch circuits included in service load calculations?
✔✔ To account for the power needs of kitchen and dining area receptacles.
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, What is the standard voltage used for residential load calculations?
✔✔ 120/240 volts.
Why is it necessary to calculate the load for HVAC systems separately?
✔✔ HVAC systems often have significant power demands that need individual consideration.
What is the purpose of calculating the feeder load for a subpanel?
✔✔ To determine the appropriate conductor size and overcurrent protection.
What does "non-coincident loads" mean in load calculations?
✔✔ Loads that do not operate simultaneously.
Why must motor loads be considered separately in feeder and service calculations?
✔✔ Motors have unique starting and running current requirements.
What is the purpose of applying a diversity factor in load calculations?
✔✔ To reflect the reduced likelihood of all loads operating at full capacity simultaneously.
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