PROJECT SUMMARY
Evaluation of Electrical Feeder and Branch Circuit Loading
27 May 2016
Background: Interest has been growing in recent years to investigate and clarify the degree to which the
feeder and branch circuit load design requirements in NFPA 70, National Electrical Code® (NEC®) need to
be adjusted based on the increasing pace of technological innovation along the entire span of the
electrical power chain. For example, today’s Energy Codes are driving down the electrical load presented
by end use equipment and thus load growth assumptions that justify “spare capacity” should be reexamined. In addition, larger than necessary transformers that supply power to feeder and branch circuits
expose unnecessary flash hazard to electricians working on live equipment.
Research Goal: The goal of this project is to develop a data collection plan to provide statistically
significant load data for a variety of occupancy and loading types to provide a technical basis for
considering revisions to the feeder and branch circuit design requirements in the National Electrical
Code®. This initial effort will have an emphasis on general commercial (office) occupancies. The
deliverables from this project represent a Phase I study to review the literature and develop a data
collection plan, in support of a potential second phase (not included in the scope of this effort).
Affected NFPA Documents: NFPA 70, National Electrical Code®, Articles 210 through 230.
Project Tasks: Following the establishment of a Project Technical Panel of subject matter experts (in
accordance with Foundation Policies) who will provide guidance during the study, the Foundation will
seek a project contractor to conduct the study in accordance with the following tasks:
1) Task 1: Review of Literature. Perform a comprehensive review of the electrical literature over
the past ten years, with a focus on previous studies on electrical loading in various occupancy
types and data that has been collected to address this topic.
2) Task 2: Development of a Detailed Data Collection Plan. Analyze and summarize the information
from Task 1 to generate a detailed data collection plan that when implemented will provide a
comprehensive evaluation of electrical feeder and branch circuit loading. The data collection plan
should be based on guidance from the Project Technical Panel and include details on proposed
scope of work, tasks (including details on collecting and analyzing data, anticipated deliverables,
and budget).
3) Task 3: Final Report.
1 Batterymarch Park, Quincy, MA 02169-7471
Telephone: +1.617.984.7281
Fax: +1.617.984.7010
Email: Foundation@NFPA.org www.NFPA.org/Foundation
A Phase 2 is anticipated and will consist of implementation of the data collection plan, its analysis and
development of recommendations related to circuit loading.
Implementation: This research program will be conducted under the auspices of the Fire Protection
Research Foundation in accordance with Foundation Policies and will be guided by a Project Technical
Panel who will provide input to the project, recommend contractor selection, review periodic reports of
progress and research results, and review the final project report. The Panel will meet by teleconference
periodically to review deliverables, provide input and assistance.
Schedule:
Task 1 - Review of Literature:
Task 2 - Draft Final Report to include data collection plan:
Task 3 - Final Report:
Two months after project initiation
Four months after project initiation
Five months after project initiation
Intellectual Property: The Research Foundation will retain rights to the project report which will be
published on the Foundation website.
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