Grounding and Bonding

Transcription

Grounding and Bonding
Grounding and
Bonding -2014
National Electrical
Code
1
Definition of Terms
and Purpose of
Grounding and
Bonding
Module 1
Definitions of Terms
• Bonded (Bonding): Connected to establish
electrical continuity and conductivity
• “Bonding Jumper”
• “Equipment Bonding Jumper”
• “Main Bonding Jumper”
• “System Bonding Jumper”
• “Supply-side Bonding Jumper”
Article 100 & 250.2
3
Definitions of Terms
• Bonding Conductor or Jumper: A reliable
conductor to ensure the required electrical
conductivity between metal parts required to
be electrically connected
• Equipment Bonding Jumper: The connection
between two or more portions of the
equipment grounding conductor
Article 100
4
Equipment Bonding Jumper
Article 100
5
Definitions of Terms
• Main Bonding Jumper: The connection between
the grounded circuit conductor and the
equipment grounding conductor at the service
• System Bonding Jumper: The connection
between the grounded circuit conductor and the
supply-side bonding jumper, or the equipment
grounding conductor, or both, at a separately
derived system
• Note that both complete the ground fault return
path to the source
Article 100
6
Main Bonding Jumper
Article 100
7
Definitions of Terms
• Supply-side Bonding Jumper
• A conductor installed on the supply side of
a service or within a service equipment
enclosure(s), or for a separately derived
system, that ensures the required electrical
conductivity between metal parts required
to be electrically connected.
250.2
8
System, Supply-side, and Equipment
Bonding Jumpers
Supply-side
Bonding jumper
9
Definitions of Terms
• Ground: The earth
• Grounded (Grounding): Connected
(connecting) to ground or a conductive body
that extends the ground connection
• Equipment grounding conductors and bonding
jumpers extend the ground connection
Article 100
10
Definitions of Terms
• Grounding: Describes elements that directly
or indirectly make connections to earth
• “Equipment Grounding Conductor”
• “Grounding Electrode”
• “Grounding Electrode Conductor”
Article 100
11
Definitions of Terms
• Equipment Grounding Conductor (EGC): The
conductive path(s) that provides a groundfault current path and connects normally non–
current-carrying metal parts of equipment
together and to the system grounded
conductor or to the grounding electrode
conductor, or both.
• Informational Note No 1: It is recognized that
the equipment grounding conductor also
performs bonding.
Article 100
12
Equipment Grounding Conductor
13
Definitions of Terms
• Grounding Electrode: A conducting object
through which a direct connection to earth is
established
• Grounding Electrode Conductor: A conductor
used to connect the system grounded
conductor or the equipment to a grounding
electrode or to a point on a grounding
electrode system
Article 100
14
Grounding Electrode and Conductors
Definitions of Terms
• Grounded Conductor: A system or circuit
conductor that is intentionally grounded
• Ungrounded (Conductor): Not connected to
ground or to a conductive body that extends
the ground connection
Article 100
16
Grounded and Ungrounded
Conductors
17
Definitions of Terms
• Neutral Point: The common point on a wye
connection in a polyphase system or midpoint
on a single-phase portion of a single-phase, 3wire system, or midpoint of a single-phase
portion of a 3-phase delta system, or a
midpoint of a 3-wire, direct-current system.
• Informational Note - this is where the vectorial
sum of voltages of all other phases using the
neutral with respect to neutral is zero
Article 100
18
Neutral Point
19
Definitions of Terms
• Neutral Conductor: The conductor connected
to the neutral point of a system that is
intended to carry current under normal
conditions
Article 100
20
Neutral Conductor and Neutral Point
21
Neutral Conductor Definition
22