Technical Specifications

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Object Dictionary An Object Dictionary (OD) contains all Function Block (FB),
Resource Block (RB) and Transducer Block (TB) parameters
used in a device. Through these parameters, the blocks can be
accessed over the fieldbus network.
OOS Out of Service mode
Out of Service State The FVP positioner transducer, resource and Analog Output,
PID blocks are in Out of Service mode.
P This is a dimensionless gain factor related to the proportioning
action of the algorithm. It ranges from 0 to 5000. Common val-
ues for the positioner are 50 for small valves up to 4000 for
large valves.
Parameter The data objects in Foundation Fieldbus are identified in the
form of TAG.PARAMETER. Each data object is a parameter
that can include many elements such as an array, or a value
and a status. Elements of a parameter are referred to by
sub-index.
PC As used in this manual, a personal computer or laptop running
under Windows 2000, Windows Server 2003 or XP operating
system.
Physical Layer The Physical Layer receives messages from the Communica-
tions Stack and converts the messages into physical signals on
the fieldbus transmission medium, and vice- versa.
PID Proportion Integral Derivative Control Block
Position With a reciprocating valve, the position is the distance of the
plug from its seat, normally measured as a linear motion of the
valve or actuator stem. With a rotary valve, the position is the
angle of rotation of the valve plug measured as angular rotation
of the valve shaft.
Position Limit The Actuator can be mechanically set to stop at a predeter-
mined position by setting an adjustment, sometimes with a
handwheel or screw stop. FVP can be configured to provide the
same limits through software control of position.
Position, Valve With a reciprocating valve, the valve position is the distance of
the plug from its seat, normally measured as a linear motion of
the valve or actuator stem. With a rotary valve the position is
the angle of rotation of the valve plug measured as angular
rotation of the valve shaft.
Positioner Tuning
Parameters
The positioner requires six integer parameters to determine the
response of the positioner to a setpoint change. Internally, the
positioner uses an improved PID control algorithm to control the
valve position.