Accuracy
The maximum positive and negative % devia-
tion over the total span.
ANSI
American National Standards Institute.
CE
Conformité Européene
Standards and performance
criteria for the new European Union.
CSA
Canadian Standards Association
Canadian,
third party agency that qualifies the safety of electrical
equipment.
Damping
The mathematical averaging of a meter and/or
output signal to stabilize the effects of a noisy process due
to surface turbulence.
Default Values
The main position of the menu structure
that displays the primary measurement values of LEVEL,
% OUTPUT, and LOOP. The transmitter returns to this
position after 5 minutes of inactivity.
Dielectric Constant (
ε
)
The electrical permitivity of a
material. The units are farad/meter.
DVM/DMM
Digital Volt Meter/Digital Multimeter.
EMI
Electromagnetic Interference
Electrical noise caused
by electromagnetic fields that may affect electrical circuits,
particularly low-power electronic devices.
EN
European Normal
Committee guidelines in EC
countries that take precedence over local, country guide-
lines.
Ergonomic
A mechanism that considers human capabil-
ity in its design or function.
Fault
A defect or failure in a circuit. The current (mA)
value unit defaults to 3.6, 22, or Hold when a diagnostic
condition occurs.
Feedthrough
A small, connecting cavity between the
main housing compartments, carrying the cable that sup-
plies the operating energy to the measurement circuitry
and returns the output value proportional to level. This
cavity is potted to maintain the environmental isolation
between the two compartments.
FM
Factory Mutual
American, third party agency that
qualifies the safety of electrical equipment.
Four Wire
An electronic instrument design that uses one
set of wires to supply power (120/240 VAC, 24 VDC)
and another set to carry the process measurement signal
(4–20 mA). Also called
Line Powered.
FSK
Frequency Shift Keying.
Ground
An electrical connection to the Earth’s potential
that is used as a reference for the system and electrical
safety.
Grounded
A state where no electrical potential exists
between the ground (green) connection on the transmitter
and the Earth or system ground.
HART
Highway Addressable Remote Transducer.
Protocol
that uses the Bell 202 frequency shift keying (FSK)
method to superimpose low level frequencies (1200/2000
Hz) on top of the standard 4–20 mA loop to provide
digital communication.
HART ID
See Poll Address.
Hazardous Area
An area where flammable gases or
vapors are or may be present in the air in quantities suffi-
cient to produce explosive or ignitable mixtures.
IEC
International Electrotechnical Commission
Orga ni zation that sets international standards for electrical
devices.
Increased Safety
Designs and procedures that minimize
sparks, arcs, and excessive temperatures in hazardous areas.
Defined by the IEC as Zone 1 environments (Ex e).
Interface: Electrical
A boundary between two related,
electronic circuits.
Interface: Process
A boundary between two or more
immiscible liquids.
Intrinsic Safety
A design or installation approach that
limits the amount of energy that enters a hazardous area
to eliminate the potential of creating an ignition source.
Level
The present reading of the height of material in a
vessel.
Linearity
The worst case error calculated as a deviation
from a perfect straight line drawn between two calibration
points.
Line Powered
See Four Wire.
Loop
The present reading of the 4–20 mA current
output.
Loop Powered
See Two Wire.
Low Voltage Directive
A European Community require-
ment for electrical safety and related issues of devices using
50–1000 VDC or 75–1500 VAC.
Measured Value
The typical level measurement values
used to track the level of a process: Level, % Output,
and Loop.
Glossary
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Kotron Model 805 Smart RF Level Transmitter
