Fisher FIELDVUE DVC2000 Instruction Manual page 67

Instruction Manual
D103176X012
Equal Percentage
A valve flow characteristic where equal
increments of valve stem travel produce equal
percentage changes in existing flow. One of the
input characteristics available for a FIELDVUE
Instrument. See also, Linear and Quick Opening.
Feedback Signal
Indicates to the instrument the actual position of
the valve. The travel sensor provides the feedback
signal to the instrument printed wiring board
assembly.
Firmware Revision
The revision number of the instrument firmware.
Firmware is a program that is entered into the
instrument at time of manufacture and cannot be
changed by the user.
Free Time
Percent of time that the microprocessor is idle. A
typical value is 25%. The actual value depends on
the number of functions in the instrument that
are enabled and on the amount of
communication currently in progress.
Full Ranged Travel
Current, in mA, that corresponds with the point
where ranged travel is maximum, i.e., limited by
the mechanical travel stops.
Gain
The ratio of output change to input change.
Hardware Revision
Revision number of the Fisher instrument
hardware. The physical components of the
instrument are defined as the hardware.
HART (acronym)
The acronym HART stands for Highway
Addressable Remote Transducer.
HART Tag
An eight‐character name that identifies the
physical instrument.
HART Universal Revision
Revision number of the HART Universal
Commands which are the communications
protocol for the instrument.
Input Characteristic
The relationship between the ranged travel and
ranged input. Possible values include: linear,
equal percentage, and quick opening.
Input Current
The current signal from the control system that
serves as the analog input to the instrument. See
also Input Signal.
Input Range
The analog input signal range that corresponds to
the travel range.
Input Signal
The current signal from the control system. The
input signal can be displayed in milliamperes or in
percent of ranged input.
Instrument Level
Determines the functions available for the
instrument. See table 3‐1.
Instrument Mode
Determines if the instrument responds to its
analog input signal. There are two instrument
modes:
In Service: For a fully functioning instrument, the
instrument output changes in response to analog
input changes. Typically changes to setup or
calibration cannot be made when the instrument
mode is In Service.
Out of Service: The instrument output does not
change in response to analog input changes
when the instrument mode is Out of Service.
Some setup parameters can be changed only
when the instrument mode is Out of Service.
Glossary
June 2017
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