2005 NEC Changes Summary
Articles 400 to 411
Mike Holt's 2005 NEC Changes Summary
Articles 400 through 411
Chapter 4 Equipment For General Use
With the first three Chapters behind
you, the final Chapter in the NEC for building a solid foundation in general work is Chapter
4. This chapter helps you apply the first three chapters to general equipment. These first
four Chapters follow a natural sequential progression. Each of the next four Chapters-5,
6, 7, and 8-builds upon the first four, but in no particular order. You do not need to
understand any of the other "next Chapters" to work with any one of them. But
you do need to understand all of the first four Chapters to properly apply any of the
Chapter 4 has some logical arrangement
of its own. Here are the groupings:
- Flexible cords and cables, fixture
wires, switches, receptacles
- Switchboards and panel boards
- Lamps, lighting, appliances, and
- Motors, refrigeration equipment,
generators, and transformers
- Capacitors and other components
These groupings make sense. For example,
motors, refrigeration equipment, generators, and transformers are all inductive equipment.
This logical arrangement of the NEC
is something to keep in mind when you're searching for a particular item. You know, for
example, that transformers are general equipment. So you would find the Code requirements
in Chapter 4. You know they are wound devices. So, you would find transformer requirements
located somewhere near motor requirements. Refrigeration equipment in the NEC means hermetically
sealed motors. So the requirements should logically be located right next to motor requirements.
And that's exactly where they are.
ARTICLE 400 Flexible Cords and Cables
This article covers the general requirements,
applications, and construction specifications for flexible cords and flexible cables.
The NEC doesn't consider flexible cords to be wiring methods like those defined in Chapter
Article 400 applies only to the cord and cable types listed in Table 400.4.
Always use a cord (and fittings) identified for the application. For example, use cords
listed for a wet location if you're using the cord outdoors in a wet location. The jacket
material of any cord is tested to maintain its insulation properties and other characteristics
only in the environments for which is has been listed.
This textbook doesn't go into detail
about Table 400.4, but you should take a few moments to review it. It's not limited to
extension cords-three of the entries are for elevator cables. You do not need to memorize
this table, but do become aware of the types of cords and cables it covers.
- New rule requires conductor
ampacity correction when cords are used in an ambient temperature above 86°*F.
- New requirement makes it clear
that cable must not be subjected to physical damage.
- New paragraph permits protected
flexible cords or cables to be installed in above ground raceways in industrial environments
in lengths up to 50 ft, but only under restricted conditions.
ARTICLE 404 Switches
The requirements of Article 404 apply
to switches of all types, such as snap (toggle) switches, dimmers, fan switches, knife
switches, circuit breakers used as switches, and automatic switches. Automatic switches
include those used as time clocks and timers, plus switches and circuit breakers used
for disconnecting means.
Here are a few key points to remember:
- Enclosures for switches or circuit
breakers can contain splices if you meet certain conditions.
- Observe the wet locations requirements.
These include locations subject to saturation with water such as those near some showers,
tubs, and pools.
- Observe switch grouping and accessibility
- Observe requirements for mounting,
marking, grounding, orientation, rating, and labeling of various kinds of switches.
- Exception revised to permit
metal switch cover plates at an outlet box where a grounding (bonding) means doesn't
exist, but only where the circuit conductors for the switch are GFCI protected.
ARTICLE 406 Receptacles, Cord Connectors,
and Attachment Plugs (Caps)
This article covers the rating, type,
and installation of receptacles, cord connectors, and attachment plugs (cord caps). It
also addresses their grounding requirements. Some key points to remember include:
Follow the grounding requirements of
the specific type of device you're using.
- Use GFCIs where specified by 406.3(D)(2),
and install per manufacturer's instructions.
- Mount receptacles per the requirements
of 406.4. These are highly detailed.
- Text added to recognize the generally
accepted practice, that receptacles mounted in boxes supported by a pendant flexible
cord is permitted.
- New Rule address flanged inlets
used for plugs and cord connectors and change treats the newly added flanged outlet
the same as an attachment plug, by requiring that exposed parts be nonenergized.
- The word "outdoors"
was deleted from this rule. The effect? All 15 and 20A 125V and 250V receptacles installed
in a wet location (indoor or outdoor) must be within an enclosure that is weatherproof
when an attachment plug is inserted.
- The requirement that an enclosure
for a receptacle be made weatherproof by providing a watertight connection between
the plate and the finished surface was expanded to include surfaces other than walls
ARTICLE 408 Switchboards and Panelboards
Article 408 covers the specific requirements
for switchboards, panelboards, and distribution boards that control light and power circuits.
Some key points to remember:
- One objective of Article 408 is
that the installation prevents contact between current-carrying conductors and people
or maintenance equipment.
- The circuit directory of a panelboard
must clearly identify the purpose or use of each circuit that originates in that panelboard.
- You must know the difference between
a "lighting and appliance panelboard" and a "power panelboard."
- You must understand the detailed
grounding and bonding requirements for panelboards.
- This section on circuit identification
was rewritten to improve safety by ensuring that workers don't have to guess which
breaker operates what circuit.
- New section specifies that unused
openings for circuit breakers and switches must be closed in a manner approved by
the authority having jurisdiction to restrict access to energized parts when the equipment
is fully assembled.
ARTICLE 410 Luminaires (Lighting
Fixtures), Lampholders, and Lamps
This article covers luminaires, lampholders,
pendants, and the wiring and equipment of such lamps and luminaires.
This article is highly detailed, but
it's broken down into ten Parts. The first five are sequential, and apply to all luminaires,
lampholders, and lamps: General, Location, Boxes and Covers, Supports, and Grounding (Bonding).
This is mostly mechanical information, and it's not hard to follow or absorb. Part VI,
Wiring, ends the sequence. The seventh, ninth, and tenth Parts provide requirements for
manufacturers to follow-use only equipment that conforms to these requirements. Part VIII
provides requirements for Installing Lampholders. The rest of Article 410 addresses specific
types of lighting.
Article 410 doesn't include "Lighting Systems Operating at 30 Volts or Less,"
Article 411 addresses them.
- The scope of Article 410 has
been expanded to include decorative lighting products, lighting accessories for temporary
seasonal and holiday use, and portable flexible lighting products.
- Strings of lights enclosed in
flexible plastic (flexible lighting products), provided with a power supply cord with
a fused attachment plug and intended for outline and decorative lighting (often known
as rope lights) must now be installed in accordance with Article 410.
- The text was modified to clarify
the types of luminaires not permitted within 3 ft horizontally and 8 ft vertically
from the top of the bathtub rim or shower stall. And new rule requires luminaires
in bathtub or shower zone to be listed for damp locations, or listed for wet locations
where subject to shower spray.
- New subsection added to clarify
when a lamp shield for mechanical protection is required for mercury vapor or metal
- Additional text clarifies that
the branch-circuit wiring is required to be accessible when electric-discharge luminaires
are surface mounted over concealed outlet boxes.
- Additional text clarifies that
flexible cords with manufactured wiring system connectors (Relox®) can be used
for the installation of electric-discharge luminaires [604.6(A)(3)].
- New requirement address the
installation of recessed Non-Type IC luminaires where insulation is required or planned.
- New rule specifies when luminaires
with metal halide lamp are to be provided with a method to help contain the arc at
end-of-life arc-tube failures.
- New rule to require disconnecting
means for fluorescent luminaires that have double-ended lamps and contain ballast(s),
but this doesn't become effective until January 1, 2008.
- Decorative lighting is now required
to be listed.
ARTICLE 411 Lighting Systems Operating
at 30 Volts or Less
- Low-voltage lighting systems
installed concealed or through a building wall are no longer required to be installed
in a Chapter 3 wiring method. Class 2 cables (CL2) are now permitted to be used for