Nace CP 1, Руководство по эксплуатации

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RP0177-2000
NACE International 1
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Section 1: General
1.1 This standard presents acknowledged practices for
the mitigation of alternating current (AC) and lightning
effects on metallic structures and corrosion control
systems.
1.2 This standard covers the procedures for determining
the level of AC influence and lightning effects to which an
existing metallic structure may be subjected and outlines
design, installation, maintenance, and testing procedures
for cathodic protection systems on structures subject to
AC influence.
1.3 This standard does not designate procedures for any
specific situation. The provisions of this standard should
be applied under the direction of competent persons,
who, by reason of knowledge of the physical sciences
and the principles of engineering and mathematics,
acquired by professional education and related practical
experience, are qualified to engage in the practice of
corrosion control on metallic structures. Such persons
may be registered professional engineers or persons
recognized as being qualified and certified as corrosion
specialists by NACE International if their professional
activities include suitable experience in corrosion control
on metallic structures.
1.4 This standard should be used in conjunction with the
references contained herein.
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Section 2: Definitions
2.1 Definitions presented in this standard pertain to the
application of this standard only. Reference should be
made to other industry standards where appropriate.
AC Exposure: Alternating voltages and currents induced
on a structure because of the alternating current (AC)
power system.
AC Power Structures: The structures associated with
AC power systems.
AC Power System: The components associated with the
generation, transmission, and distribution of alternating
current.
Affected Structure: Pipes, cables, conduits, or other
metallic structures exposed to the effects of alternating
current and/or lightning.
Bond: A low-impedance connection (usually metallic)
provided for electrical continuity.
Breakdown Potential: A voltage potential in excess of
the rated voltage that causes the destruction of a barrier
film, coating, or other insulating material.
Capacitive Coupling: The association of two or more
circuits with one another by means of a capacitance
mutual to the circuits.
Coupling: The association of two or more circuits or
systems in such a way that energy may be transferred
from one to another.
Dead-Front Construction: A type of construction in
which the energized components are recessed or covered
to preclude the possibility of accidental contact with
elements having electrical potential.
Direct Current (DC) Decoupling Device: A device used
in electrical circuits that allows the flow of AC in both
directions and stops or substantially reduces the flow of
DC.
Earth Current: Electric current flowing in the earth.
Electric Field: One of the elementary energy fields in
nature. It is found in the vicinity of an electrically charged
body.
Electric Potential: The voltage difference between two
points.
Electric Shield: A housing, screen, or other object,
usually electrically conductive, which is installed to
substantially reduce the effects of electric fields on one
side caused by devices or circuits on the other side of the
shield.
Electrolytic Grounding Cell: A DC decoupling device
consisting of two or more electrodes, commonly made of
zinc, installed at a fixed spacing and resistively coupled
through a prepared backfill mixture.
Fault Current: A current that flows from one conductor
to ground or to another conductor due to an abnormal
connection (including an arc) between the two. A fault
current flowing to ground may be called a ground fault
current.