Marcelo Valdes
GE Electrical Distribution
Manager of
Application Engineering |
A brief Q&A with Marcelo Valdes, Manager of
Application Engineering at GE’s Electrical
Distribution headquarters in Plainville, CT,
regarding the National Electrical Code (NEC)
2008, made available as of January 2008.
Q: Good Day
Marcelo — Can you describe for us the
information source for the National
Electrical Code?
A: The book
known as the National Electrical Code is
published by the National Fire Protection
Association (NFPA). It is officially known
as NFPA 70. It undergoes a 32-year long
editing and review process every three
years. The public is invited to contribute
and comment at specific times within that
3-year time period. Once it is published, it
is up to the states and local jurisdiction
to adopt it and give it the power of law.
Prior to it being adopted by the state or
local jurisdiction having authority, the NEC
has no validity, except as an advisory
document.
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Q: What is the
NFPA’s intent in creating the code?
A: The primary concern
of the NFPA in publishing the code is the protection
of life and property—in other words, safety for both
electricians and the public.
Q: How does the
NFPA implement and enforce codes nationally?
A: The simple answer
is that they don’t. Their role is purely advisory.
Adoption and enforcement are solely at the
discretion of states and municipalities who make the
laws. This is why adoption and consequentially
enforcement generally lags the publishing of codes
by as much as several years and varies greatly by
geography. So beyond understanding the NEC 2008
Code, it’s important to know what your local
jurisdiction having authority (JHA) is enforcing.
Q: What would you
highlight as important updates since the NEC 2005
Code?
A: There are many
significant changes. Two updates that are drawing a
lot of attention from the perspective of circuit
breaker manufacturers
1. Selectivity Requirements in articles 700,
701 and 708 (a completely new section)
2. Arc Fault Protection for Dwellings
Q: Selectivity
seems to be of growing importance throughout the
country but confusing to many. Can you describe in
simple, basic terminology the meaning of a
“selective system”?
A: Sure, in it’s most
basic description, it is a system designed such that
when a portion of the electrical system experiences
a fault, only the overcurrent closest to that fault
will open or trip, shutting off power to that
circuit and only that circuit. All other overcurrent
devices stay closed allowing all unfaulted parts of
the system to remain energized. Most people in their
homes would have a selectively coordinated system,
such that if you were operating multiple hair dryers
in the bathroom that caused a circuit breaker to
trip, you would only lose power in that room versus
the entire house.
Q: How has NEC 2008
been updated with regards to selectivity?
A: This was a new
requirement in 2005 for Emergency Systems and
Legally Required Standby Systems. In 2008, some
exceptions were added to exclude circuit
configurations that do not need to be selective, and
it was added to the new article 708 Critical
Operations Power Systems — a completely new section
directed to homeland defense-related facilities or
other critical facilities such as 911-call centers.
Q: What is the
implication of this for the industry?
A: It is affecting the
overall design of electrical systems including the
selection of the protection components. In a system
seeking to meet the code requirements, the design
and component selection can be much more complex. It
requires a greater diligence by engineers and those
selling electrical systems to create the system so
that selectivity can be achieved and the right
components can be selected. It can put a lot of
burden and risk on the shoulders of sales engineers
and anybody responsible for choosing exactly the
right circuit breaker for every circuit.
Q: That does sound
important. What about the second topic you
mentioned: Arc Fault Protection for Dwellings? What
is that?
A: This is primarily
focused on residential dwellings. First introduced
with NEC 1999, arc fault circuit interrupting (AFCI)
breakers were a code mandated requirement for
bedrooms. The 2008 code includes two key changes:
1. A change in the breaker technology and
2. The expansion of the requirement to
include “all dwelling areas” of the home.
Q: So NEC 2008
compliant AFCI breakers are different from
previously available AFCI breakers in terms of the
technology?
A: Yes, they offer
greater protection. The new breakers are commonly
referred to as “combination” arc fault devices.
Previous versions detected only “parallel” faults,
which is the unintentional flow of electricity
between two separate wires. The NEC 2008 compliant
arc fault breakers detect not only parallel faults
but also “series” faults, which are the unintended
flow of electricity over a gap within a single wire.
Q: Additionally, it
looks like the code expands the use of these new
breakers beyond the bedroom circuits. How will this
change the typical residential job?
A: The 2008 NEC® Code
mandates that all dwelling areas in the home have
Combination AFCI protection, including rooms such as
living rooms, dining rooms, hallways, closets, dens,
finished basements, sun rooms in addition to the
bedrooms. In a typical 3-bedroom house where you
previously may have had 2 – 3 AFCI breakers, you now
will likely require 8 – 10 of the combination AFCI
breakers.
Q: Thank You
Marcelo for your time and insights.
A: My pleasure. At GE
it’s important to drive awareness and education on
important topics like code compliance within the
industry.
|
GE Joins The Green Grid, Shares
Environmentally Conscious Practices for Data
Centers |
GE Consumer & Industrial has joined The Green Grid, a
global consortium of more than 80 high-tech equipment
companies, including AMD, APC, Dell, HP, IBM, Intel,
Microsoft, Rackable Systems, SprayCool, Sun Microsystems
and VMware. GE will work closely with other members of
The Green Grid to develop meaningful operating
standards, metrics and technologies to improve the
energy efficiency and performance of data centers and
computing ecosystems.
“Environmental initiatives are in the fabric of GE,”
says Timothy Connolly, sales development manager,
mission critical team, GE Consumer & Industrial. “ We
are fully aware of today’s challenges in the data center
industry. Our membership in The Green Grid demonstrates
our commitment to developing more energy-efficient data
centers.”
GE currently offers a wide range of practical solutions
designed to improve the energy efficiency and reduce the
overall operational costs of data centers. In 2005, GE
launched “ecomagination,” a GE initiative to
aggressively bring to market new technologies that help
customers and consumers meet pressing environmental
challenges.
For more information about GE’s involvement with
The Green Grid or data center services, please
contact:
Timothy.Connolly@ge.com or visit
www.geelectrical.com/datacenters.