IEEE 81.2-1991
IEEE Guide for Measurement of Impedance and Safety Characteristics of Large, Extended or Interconnected Grounding Systems
standard by IEEE, 06/25/1992
Most Recent
Language:
-
- Available Formats
- Options
- Availability
- Priced From ( in USD )
-
- Immediate download
- $210.00
- Add to Cart
Customers Who Bought This Also Bought
-
IEEE 80-2013
Priced From $195.00 -
IEEE 81-2012
Priced From $136.00 -
IEEE 367-2012
Priced From $241.00 -
IEEE 487-2015
Priced From $150.00
About This Item
Full Description
Scope
Test methods and instrumentation techniques used to measure the ac characteristics of large grounding systems
include the following topics:
1) Measurement safety
2) Earth-return mutual errors
3) Low-current measurements
4) Power-system staged faults
5) Communication and control cable transfer impedance
6) Current distribution (current splits) in the grounding system
7) Step, touch, mesh, and proA?le measurements
8) The foot-equivalent electrode earth resistance
9) Instrumentation characteristics and limitations
Grounding electrodes consisting of a single ground rod, arrays of ground rods, tower footings, and many grids (if no
external grounding is connected) can be measured, interference voltages permitting, with methods outlined in IEEE
Std 81-1983 [2]
1
. Even if a large grid has an impedance phase angle of 18
¿¿
the resistance component will be only 5%
lower than its impedance. However, for large grounding grids in low-resistive earth (<75
W
-m) and for grounding systems that have numerous extended grounding conductors, the impedance could be signiA?cantly greater than the
resistive component measured with the conventional test sets of IEEE Std 81-1983
Purpose
The purpose of this guide is to present practical instrumentation methods that may be used for the measurement of
impedance to remote earth, step and touch potentials, and current distributions of large extended or interconnected
grounding systems ranging in complexity from small grids (less than 900 m
2
), with only a few connected overhead or
direct burial bare concentric neutrals, to large grids (greater than 20 000 m
2
), with many connected neutrals, overhead
ground wires (sky wires), counterpoises, grid tie conductors, cable shields, and metallic pipes.
Abstract
New IEEE Standard - Inactive-Withdrawn.
Practical instrumentation methods are presented for measuring the ac characteristics of large,
extended or interconnected grounding systems. Measurements of impedance to remote earth, step and
touch potentials, and current distributions are covered for grounding systems ranging in complexity from small grids (less than 900m 2), with only a few connected overhead or direct burial bare concentric (2) neutrals, to large grids (greater than 20 000m 2), with many connected neutrals, overhead ground wires (sky wires), counterpoises, grid tie conductors, cable shields, and metallic pipes. This standard addresses measurement safety; earth-return mutual errors; low-current measurements; power-system staged faults; communication and control cable transfer impedance; current distribution (current splits) in the grounding system; step, touch, mesh, and profile measurements; the foot-equivalent electrode earth resistance; and instrumentation characteristics and limitations.
