Transcript Article 100 - Draves Electrical Class

Electrical Code Definitions
Understanding Code
• Wiring components are
considered accessible when
access is gained without
damaging the structure.
• Example: Conductors
connected to switches and
receptacles are accessible
by a removable plate or
device.
If you can move this dresser, and it
has a cover plate it’s accessible
• Accessible equipment is
equipment not guarded by
locked doors, elevators, or
other.
• Exception: Overcurrent
devices don not have to be
readily accessible if located
adjacent to the equipment
where access is achieved by
the use of portable means.
Meaning that if you had to get a
ladder to reset this breaker, it’s
considered accessible equipment as
long as it’s not blocked.
• Readily accessible means
capable of being reached
quickly without have to
climb or remove
obstacles.
• Example: A service
disconnecting means
must be readily
accessible or near the
entry point of the service
conductor.
Bushes in front electrical components
that come under the code of readily
accessible must be cut down.
• Ready accessibility to
wiring in luminaires is not
required. In most cases,
access can be gained
through the use of a ladder
or scaffolding ect.
• Conductors: With junction
boxes of recessed
luminaires can be accessed
by removing part of the
luminaire.
As long as you can remove the trim
and access the junction box it will be
considered readily accessible!
• Utilization equipment of a commonly built-in
standard, installed as a unit such as AC, or a
stove….
• Capable of being
reached quickly for
operation, renewal, or
inspections without
climbing over or having
to remove obstacles.
A ceiling receptacle installed is not
readily accessible, and it must have a
ground-fault interrupter (GFCI) .
• A device intended to
provide protection
from the effects of arc
faults by recognizing
characteristics unique
to arcing and by deenergizing the circuit
when an arc fault is
detected.
An AFCI is basically like a GFCI but it
will protect the entire circuit from the
breaker and back.
• An attachment plug (plug cap) is a device that,
when inserted into a receptacle establishes a
connection between the conductors of a cord
and the receptacle.
• Connected to
establish electrical
continuity and
conductivity.
Bonding means that everything is connected
or conductivity of the electron through wires.
• When metal parts are
required to be electrically
connected, a reliable
conductor (Bonding Jumper) is
installed, thereby
guaranteeing electrical
conductivity.
The main bonding jumper is connection at the
service between the grounded circuit conductor
and the equipment grounding conductor.
• An Equipment bonding
jumper is the connection
between two or more
portions of the equipment
grounding conductor.
Notice the bonding jumper must be made of
copper or other corrosion-resistant material. A
wire, bus, screw, or similar suitable conductor is
acceptable as a main bonding.
• An appliance branch circuit supplies
energy to one or more outlets for the
purpose of connecting appliances.
These circuits exclude the connection of luminaires (lights)
unless they are part of the appliance being connected.
• The circuit conductors
found between a circuit’s
final overcurrent
protective device (breaker)
and the circuit’s outlet is
called a branch circuit.
Branch circuits are divided into four categories:
Appliance, General purpose, Individual, and Multi-wire.
• An individual branch
circuit supplies only
one piece of
utilization equipment.
Branch circuits are divided into four categories:
Appliance, General purpose, Individual, and Multi-wire.
• A general purpose branch
circuit supplies two or
more receptacles or
outlets for lighting and
appliances.
Here we see a general purpose branch circuit.
• A. A voltmeter will not register a
voltage when connected to the
same ungrounded (hot) phase.
• B. There a multi-wire circuit must
consists of two or more
ungrounded (hot) conductors that
have a voltage between them.
Main panel
• C. The one grounded
Neutral conductor of a
multi-wire circuit must be
connected to the neutral or
grounded conductor of the
system
Main panel
• D. All conductors of a
multi-wire branch circuit
must originate from the
same panel board or
similar distribution
equipment.
Main panel
• E. There must be only one
grounded neutral
conductor, and there must
be an equal voltage
between it and each
undergrounded conductor
of the circuit.
See 210.4 A through D for
additional requirements…
• Multi-wire circuit consists of
one (or more) duplex
receptacles, one or more
multiple receptacles single or
combination.
• A. A duplex receptacle can be
supplied by two branch
circuits by removing the tab.
This receptacle is fed from a
multi-wire branch circuit.
• B. This tab has been removed
to allow separate feeds of
each outlet.
C. Each multi-wire
branch circuit must be
provided with a means
that will simultaneously
disconnects all
ungrounded (hot)
conductors at the point
where branch circuits
originate.
• D. Although the
box contains a
multi-wire branch
circuit, only one
ungrounded (hot)
conductor is
feeding this
duplex receptacle.
See 210.70 for switch controlled
• Concealed means rendered
inaccessible by the structure of
finish of a building
• Conductors in concealed
raceways, even though they
become accessible by
withdrawing them, are still
considered concealed.
Raceway containing branch
circuit conductors in concrete
A conduit body is a
separate portion of a
conduit (tubing) system
providing access to the
interior of the system
through a removable
cover at a junction.
Conduit (Junction) Box
B. FS, FD and larger boxes
(cast or sheet metal) are not
classified as conduit bodies.
C. A single conduit is not
permitted as sole support for
an FS-type or weatherproof
junction box.
• Show FS boxes in Material PDF
FS (Ferris Box Standard)
FSS (Ferris Box Continuous)
A load having the maximum
level of current sustained for
three hours or more is
referred to as a continuous
load.
Office lighting is an example
of a continuous load.
It can apply to industrial
motor as well that run
facilities…
A unit of an electrical
system that carries or
controls electrical
energy as its principal
function is known as
a device.
Duplexes control outlets of energy, as
well as switches and can be used in
conjunction such as a garbage
disposal…
Equipment, conductors, ect., surrounded by a case,
housing, fence, or walls and it prevents people
from accidentally contacting energized parts is
referred to as “enclosed.”
Any case, housing, apparatus,
fence, or wall surrounding an
installation designed to prevent
personnel from accidentally
contacting energized parts to
protect the equipment from
physical damage serves as an
enclosure.
Enclosure for a motor starter
Equipment is a general
term, including fittings,
devices, appliances,
luminaires, apparatus,
machinery, and ect., which
is used indirectly or directly
on electrical installations.
All this can be considered
equipment…pretty much
anything sold at home depot
B. Branch Circuits…
A. A feeder consists of all circuit conductors located between
the service equipment, the source of a separately derived
system, or other power supply source and the final branchcircuit overcurrent device. B. Branch Circuits…
A. Festoon lighting is a string of outdoor
lights suspended between two points.
B. Overhead conductors for festoon lighting
shall not be smaller than 12 AWG unless
supported by messenger wires…
C. Messenger wire(s), together with insulators is used to
support conductors in all span exceeding 40ft (12m) in
length. They can’t be attached to any fire escape,
downspout or plumbing equipment.
A. A fitting is an accessory, such as a locknut or
bushing, whose function is primarily mechanical,
rather than electrical in nature.
A. A grounded conductor is a system or circuit conductor
that is intentionally grounded. Ground is defined as earth.
B. Grounded (grounding) is defined as being connected to
ground or to a conductive body that extends to the a ground
connection.
• A. Main Equipment
• B. Conductive Path
• C. Grounded Neutral
• D. Bonding Jumper
• E. Bonding Conductor
• F. Grounding Electrode
Conductor
• G. Grounding Electrode
Guarded is defined as covered, shielded, fenced, enclosed,
or otherwise protected by barriers, rails, screens, mats, or a
platform removing the approach of contact by people or
persons.
A. NEC defines in sight from, within, or within sight to the
applied equipment and indicates that specified items or
equipment is visible and not more than 50 Ft. apart.
B. A motor disconnecting means must be located in sight from
the motor location as required by 430.102
A. An outlet intended for the direct connection of a
lamp holder or luminaire is called a lighting outlet.
A. Damp locations are those subject to moderate
degrees of moisture. Exterior protected locations under
canopies, roofs, porches, and similar sites are
considered damp locations.
A. Dry locations are those not
normally subject to moisture
except on a temporary basis
such as a building under
Construction…
•
NEC
A luminaire is a complete
lighting unit consisting of a
light source such as a lamp or
lamps, together with the parts
designed to position the light
source and connect it to the
power supply.
It may also include parts to
protect the light source ballast
or distribute the light.
A lamp holder itself is not a
luminaire.
A. A surface, flush, or freestanding raceway
designed to hold conductors and receptacles (in
the field or the factory).
A. Installations in any of the following categories are wet
locations, underground, within concrete slabs, in masonry
areas subject to saturation or liquids and in locations
unprotected from weather.
A. The neutral point is the common point
on a Wye-connection in a polyphase system.
B. The neutral point is the midpoint on a
single-phase portion of a 3 wire system.
C. The neutral point is the midpoint on a
single-phase portion of a 3 phase Delta
System.
D. The neutral point is the midpoint on a
single-phase portion of a 3 wire direct
current system.
A point in a wiring system from which current is
taken to supply utilization equipment is known as
an outlet.
Overcurrent Protection
(Breaker)
A branch-circuit overcurrent protection is a device capable
of protecting feeders, branch circuits, service equipment
between its rated current and its interrupting rating.
A. The space above a suspended ceiling used for
environmental air-handling purposes is an example of
other space used for environmental air described in 300.22
B. A compartment or chamber having one or
more attached air ducts and forming the
distribution system is known as a plenum.
A. A contact device installed at an outlet for the
connection of an attachment plug is a receptacle.
B. A separately derived system is a premises wiring system
whose power is derived from a source of electric energy or
equipment other than a service. It has no direct
connection from circuit conductors.
A. The conductors and
equipment that deliver energy
from the serving utility to the
wiring system of the premises
are called the service…
A. The conductors from
the service point to the
service disconnecting
means are known as
service conductors…
A. The overhead conductors between
the utility electric supply and the
service point.
A. Service equipment is that equipment (circuit breaker),
switches, fuses, and other that is necessary to constitute
the main control and cutoff that is connected to the load
end of the service conductors.
A. The service lateral is the underground
conductors between the utility electric
supply system and the service point.
A. The service point is the point of
connection between the facilities of the
serving utility and the premises wiring.
Special permission is the written consent of
the authority having Jurisdiction or the AHJ
who enforce the NEC and grant variances in
the code (building department).
Multi-Wire
A ____ branch circuit supplies two
or more receptacles or outlets for
lighting and appliances?
False
Not readily accessible means you
don’t have to worry about it at all
or ever have to service it? T/F
False
A grounded conductor is a jumper
to the main box on a feeder tube.