Appendix I Glossary - Cont'd -141200436

FAIL-- The loss of the control signal or power to a

ELECTROLYTIC SOLUTION-- A solution that

component. Also, the breakage or breakdown of a

conducts electric current by the movement of ions.

component or component part.

ELECTROMAGNET-- An electrically excited

FAIL POSITION-- The operating or physical position

magnet capable of exerting mechanical force or of

to which a device will go upon loss of its control

performing mechanical work.

signal.

ELECTROMAGNETIC-- The term describing the

FEEDBACK-- A value derived from a controlled

relationship between electricity and magnetism;

function and returned to the controlling function.

having both magnetic and electric properties.

FERROMAGNETIC MATERIAL-- A highly

ELECTROMAGNETIC INDUCTION-- The pro-

magnetic material, such as iron, cobalt, nickel, or

duction of a voltage in a coil due to a change in the

alloys.

number of magnetic lines of force (flux linkages)

passing through the coil.

FIELD OF FORCE-- A term used to describe the total

force exerted by an action-at-a-distance

ELECTROMOTIVE FORCE (emf)-- The force

phenomenon, such as gravity upon matter, electric

(voltage) that produces an electric current in a

charges acting upon electric charges, magnetic

circuit. The force that causes electricity to flow

forces acting upon other magnets or magnetic

between two points with different electrical charges

materials.

or when there is a difference of potential between

FIXED RESISTOR-- A resistor having a definite

the two points. The unit of measurement is volts.

resistance value that cannot be adjusted.

ELECTRON-- The elementary negative charge that

FLUX-- In electrical or electromagnetic devices, a

revolves around the nucleus of an atom.

general term used to designate collectively all the

ELECTRON SHELL-- A group of electrons that have

electric or magnetic lines of force in a region.

a common energy level that forms part of the outer

FLUX DENSITY-- The number of magnetic lines of

structure (shell) of an atom.

force passing through a given area.

ELECTROSTATIC-- Pertaining to electricity at rest,

FREQUENCY METER-- A meter used to measure

such as charges on an object (static electricity).

the frequency of an ac signal.

ELECTROSTATIC METER MOVEMENT-- A

FUNCTION-- To perform the normal or characteristic

meter movement that used the electrostatic

action of something, or a special duty or

repulsion of two sets of charged plates (one fixed

performance required of a person or thing in the

and the other movable). This meter movement

course of work.

reacts to voltage rather than to current and is used

GALVANIC CORROSION-- Corrosion of a metal

to measure high voltage.

because of electrical contact with a more noble

ELEMENT-- A substance, in chemistry, that cannot be

metal or nonmetallic conductor in a corrosive

divided into simpler substances by any means

environment. Often used to refer specifically to

ordinarily available.

bimetallic corrosion; sometimes called couple

action.

EMBRITTLEMENT-- Severe loss of ductility of a

metal or alloy.

GALVANIC COUPLE-- Two or more dissimilar

conductors, commonly metals, in electrical contact

EMERGENCY-- An event or series of events in

in the same electrolytic solution.

progress that will cause damage to equipment

unless immediate, timely, and correct procedural

GALVANIC SERIES-- A list of metals and alloys

steps are taken.

arranged according to their relative corrosion

potentials in a given environment. Note that this

EXTERNAL CIRCUIT-- Wires, connectors,

may not be the same order as in the electromotive

measuring devices, current sources, and so forth,

force series.

that are used to bring about or measure the desired

electrical conditions within the test cell. Also

GALVANOMETER-- A meter used to measure small

values of current by electromagnetic or

known in corrosion parlance as that part of an

electrodynamics means.

electrochemical cell external to the solution.

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