Glossary - Fisher FIELDVUE DVC6200 Instruction Manual

Instruction Manual
D103605X012

Glossary

Alert Point
An adjustable value that, when exceeded,
activates an alert.
Algorithm
A set of logical steps to solve a problem or
accomplish a task. A computer program contains
one or more algorithms.
Alphanumeric
Consisting of letters and numbers.
Analog Input Units
Units in which the analog input is displayed and
maintained in the instrument.
ANSI (acronym)
The acronym ANSI stands for the American
National Standards Institute
ANSI Class
Valve pressure/temperature rating.
Bench Set
Pressure, supplied to an actuator, required to
drive the actuator through rated valve travel.
Expressed in pounds per square inch.
Byte
A unit of binary digits (bits). A byte consists of
eight bits.
Calibration Location
Where the instrument was last calibrated; either
in the factory or in the field.
Configuration
Stored instructions and operating parameters for
a FIELDVUE Instrument.
Control Loop
An arrangement of physical and electronic
components for process control. The electronic
components of the loop continuously measure
one or more aspects of the process, then alter
those aspects as necessary to achieve a desired
process condition. A simple control loop
measures only one variable. More sophisticated
control loops measure many variables and
maintain specified relationships among those
variables.
Control Mode
Defines where the instrument reads its set point.
The following control modes are available for a
FIELDVUE Instrument:
Analog The instrument receives its travel set
point over the 4‐20 mA loop.
Digital The instrument receives its set point
digitally, via the HART communications link.
Test This is not a user‐selectable mode. The Field
Communicator or ValveLink software places the
instrument in this mode whenever it needs to
move the valve, such as for calibration or
diagnostic tests.
Control Mode, Restart
Determines the instrument control mode after a
restart. See Control Mode for the available restart
control modes.
Controller
A device that operates automatically to regulate a
controlled variable.
Current‐to‐Pressure (I/P) Converter
An electronic component or device that converts
a milliamp signal to a proportional pneumatic
pressure output signal.
Cycle Counter
The capability of a FIELDVUE instrument to record
the number of times the travel changes direction.
The change in direction must occur after the
deadband has been exceeded before it can be
counted as a cycle.
Glossary
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