Chapter 6 Flashcards
Installing CP Components
What is the purpose of a test station?
to provide access for the measurement of the effectiveness of a cathodic protection system
Potential measurement stations are used for
monitoring effectiveness of cathodic protection, check for stray current effects, locate areas of corrosion on partially protected or unprotected pipelines
An isolating joint should not be installed where ____-
an explosive or combustible environment is present.
If it must be installed in that area make sure a surge protector is used
Polarization coupons are made
from the same material as the structure
A common method of attaching wires and cables to a structure
thermite (exothermic) welding
_________ should not be used to connect wires to a structure
brazing
Galvanic anodes operate because of
the galvanic(dissimilar metal) reaction between the anode and the structure
aluminum alloy anodes are used primarily in
seawater. Aluminum is preferred in seawater because it has a much lower consumption rate than magnesium or zinc
anode efficiency
The efficiency of a galvanic anode is the ratio of an anode weight sacrificed for CP purposes divided by the total theoretical ampere-hours or capacity of the material used
Galvanic anode backfill consists of
75% gypsum, 20% bentonite, and 5% sodium sulfate
__________ anodes must be attached to the structure through a metallic conductor
galvanic anodes
Surface groundbeds are those where anodes are installed either vertically or horizontally at a depth of typically
5 to 15 feet below the surface
Deep anode installations are installed vertically at a depth of
15 meters(50 ft) or below
Rectifiers that lack a transformer and use solid state circuitry to reduce incoming power are called
switchmode rectifiers
THe anode should be connected to the _____ terminal
positive
