TotalFlow XRC6490, User Manual

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B-30
TERM DEFINITION
Membrane The pH-sensitive glass bulb is the membrane across which the potential
difference due to the formation of double layers with ion-exchange properties
on the two swollen glass surfaces is developed. The membrane makes contact
with and separates the internal element and filling solution from the sample
solution.
Memory Electronic devices that enable a computer to store and recall information. In its
broadest sense, memory refers to any hardware capable of serving that end,
e.g., disk, tape, or semiconductor storage.
Menu The list of available functions for selection by the operator, usually displayed on
the computer screen once a program has been entered.
MEPAFLOW SICK Engineering’s Menu-based Measurement and Parameterization Software
for the TotalSonic system (MMI).
Mercaptans Compounds of carbon, hydrogen and sulfur found in sour crude and gas; the
lower mercaptans have a strong, repulsive odor and are used, among other
things, to odorize natural gas.
Meter Acronym M. Metric measurement equal to 1.09361 yards.
Meter Manifold Gas piping between gas service line and meter. Also, gas piping supplying two
or more meters.
Meter, Orifice A meter using the differential pressure across an orifice plate as a basis for
determining volume flowing through the meter. Ordinarily, the differential
pressure is charted.
Meter, PD See Meter, Positive Displacement.
Meter, Positive
Displacement An instrument which measures volume on the basis of filling and discharging
gas in a chamber.
Meter, Turbine 1) Pulse meter. 2)A velocity measuring device in which the flow is parallel to the
rotor axis and the speed of rotation is proportional to the rate of flow. The
volume of gas measured is determined by the revolutions of the rotor and
converting them to a continuously totalized volumetric reading.
Methane (C1H4) A hydrocarbon (Alkane) with the lightest molecule. A gas under normal
conditions. The first of the paraffin series of hydrocarbons. The chief constituent
of natural gas. Pure methane is odorless and has a heating value of 1012 Btu
per cubic foot. Typically mixed with a sulfur compound to aid in leak detection.
microFlo Computer
See
µ
FLO.
Microprocessor This term is commonly used to describe the CPU. More specifically, it refers to
the part of the CPU that actually does the work, since many CPUs now contain
L1 and L2 caches on-chip.
Milli One thousandth e.g. one milli-watt - 1mW. one milli-amp - 1mA. one milli-volt -
1mV.
Millimeter Acronym mm. Metric measurement equal to .03937 inch.
MIPS Million instructions per second. The unit for expressing the speed of processor
machine code instructions.
Mj Abbreviation for megajoule, equivalent to one million joules.
Mm Acronym for Millimeter.
MMBtu A thermal unit of energy equal to 1,000,000 Btu’s, that is, the equivalent of
1,000 cubic feet of gas having a heating content of 1,000 BTUs per cubic foot,
as provided by contract measurement terms.
MMcf A million cubic feet. See CUBIC FOOT. (1,000,000 CF)
MMI See Man-Machine Interface.