User`s manual

7800 Series Hysteresisgraph System User's Manual
Glossary of Terminology A-3
gilbert (Gb). A cgs electromagnetic unit of the magnetomotive force required to produce one maxwell of magnetic flux in a magnetic
circuit of unit reluctance. One gilbert is equal to 10/4π ampere-turn. Named for William Gilbert (1540
– 1603), an English
physicist; hypothesized that the earth is a magnet.
gilbert per centimeter. Practical cgs unit of magnet intensity. Gilberts per cm are the same as oersteds.
Greek alphabet. The Greek alphabet is defined as follows:
Alpha α Α Iota ι Ι Rho ρ Ρ
Beta β Β Kappa κ Κ Sigma σ Σ
Gamma γ Γ Lambda λ Λ Tau τ Τ
Delta δ ∆ Mu µ Μ Upsilon υ Υ
Epsilon ε Ε Nu ν Ν Phi φ Φ
Zeta ζ Ζ Xi ξ Ξ Chi χ Χ
Eta η Η Omicron ο Ο Psi ψ Ψ
Theta θ Θ Pi π Π Omega ω Ω
ground. A conducting connection, whether intentional or accidental, by which an electric circuit or equipment is connected to the
earth, or to some conducting body of large extent that serves in place of the earth. Note: It is used for establishing and maintaining
the potential of the earth (or of the conducting body) or approximately that potential, on conductors connected to it, and for
conducting ground current to and from the earth (or of the conducting body).
2
H. Symbol for magnetic field strength. See Magnetic Field Strength.
Hall effect. The generation of an electric potential perpendicular to both an electric current flowing along a thin conducting material
and an external magnetic field applied at right angles to the current. Named for Edwin H. Hall (1855
– 1938), American physicist.
Hall mobility. The quantity µH in the relation µH = Rσ, where R = Hall coefficient and σ = conductivity.
2
hard disk drive (HDD).
hazard communication standard (HCS). The OSHA standard cited in 29 CFR 1910.1200 requiring communication of risks from
hazardous substances to workers in regulated facilities.
Helmholtz coils. A pair of flat, circular coils having equal numbers of turns and equal diameters, arranged with a common axis, and
connected in series; used to obtain a magnetic field more nearly uniform than that of a single coil.
1
hertz (Hz). A unit of frequency equal to one cycle per second.
hole. A mobile vacancy in the electronic valence structure of a semiconductor that acts like a positive electron charge with a positive
mass.
2
hysteresis. The dependence of the state of a system on its previous history, generally in the form of a lagging of a physical effect
behind its cause.
1
Also see magnetic hysteresis.
IEEE. Institute of Electrical and Electronics Engineers.
IEEE-488. An instrumentation bus with hardware and programming standards designed to simplify instrument interfacing. The
addressable, parallel bus specification is defined by the IEEE.
initial permeability. The permeability determined at H = 0 and B = 0.
initial susceptibility. The susceptibility determined at H = 0 and M = 0.
integrator. A circuit or network whose output waveform is the time integral of its input waveform.
1
international system of units (SI). A universal coherent system of units in which the following seven units are considered basic:
meter, kilogram, second, ampere, kelvin, mole, and candela. The International System of Units, or Système International d'Unités
(SI), was promulgated in 1960 by the Eleventh General Conference on Weights and Measures. For definition, spelling, and
protocols, see Reference 3 for a short, convenient guide.
interpolation table. A table listing the output and sensitivity of a sensor at regular or defined points which may be different from the
points at which calibration data was taken.
intrinsic coercivity. The magnetic field strength (H) required to reduce the magnetization (M) or intrinsic induction in a magnetic
material to zero.
intrinsic induction. The contribution of the magnetic material (B
i
) to the total magnetic induction (B).
B
i
= B – µ
o
H (SI) B
i
= B – H (cgs)
isolated (neutral system). A system that has no intentional connection to ground except through indicating, measuring, or protective
devices of very-high impedance.
2
Kelvin (K). The unit of temperature on the Kelvin Scale. It is one of the base units of SI. The word “degree” and its symbol (°) are
omitted from this unit. See Temperature Scale for conversions.
Kelvin Scale. The Kelvin Thermodynamic Temperature Scale is the basis for all international scales, including the ITS-90. It is fixed
at two points: the absolute zero of temperature (0 K), and the triple point of water (273.16 K), the equilibrium temperature that pure
water reaches in the presence of ice and its own vapor.
line regulation. The maximum steady-state amount that the output voltage or current will change as the result of a specified change in
input line voltage (usually for a step change between 105
– 125 or 210 – 250 volts, unless otherwise specified).