User`s manual

Lake Shore MTD Series Cryotest System User’s Manual
A-4 Glossary of Terminology
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 relatively 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), an American physicist.
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.
hertz (Hz). A unit of frequency equal to one cycle per second.
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.
I.D. Inner diameter.
IEC. International Electrotechnical Commission.
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.
infrared (IR). For practical purposes any radiant energy within the wavelength range 770 to 10
6
nanometers is
considered infrared energy.
2
The full range is usually divided into three sub-ranges: near IR, far IR, and
sub-millimeter.
input card. Electronics on a printed circuit board (card) that plug into an instrument main frame. Used by configurable
instruments to allow for different sensor types or interface options.
interchangeability. Ability to exchange one sensor or device with another of the same type without a significant change
in output or response.
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)
IPTS-68. International Practical Temperature Scale of 1968. Also abbreviated as T
68
.
isolated (neutral system). A system that has no intentional connection to ground except through indicating, measuring,
or protective devices of very-high impedance.
2
ITS-90. International Temperature Scale of 1990. Also abbreviated as T
90
. This scale was designed to bring into as close
a coincidence with thermodynamic temperatures as the best estimates in 1989 allowed.
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.
LCC. Leadless Chip Carrier.
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).
line voltage. The RMS voltage of the primary power source to an instrument.