Masoneilan SVI II AP Installation and Maintenance ... - GE Energy

Glossary
F
Accuracy
Actuator
Type
Algorithm
ATC Air to
Close
ATO Air to
Open
CALIBrate
In a control valve the position is measured between mechanical motion limits
in the valve. These limits can include position variations due to actuator and
valve rigidity. therefore, accuracy is referenced to positions within normal
travel of the valve independent of rigidity effects at the mechanical limits.
Accuracy is the greatest deviation from the expected position within the normal
travel, expressed as percent of normal travel.
An actuator is a device that transforms an input signal (mainly an electrical
signal) into motion. A HART compliant actuator receives a 4 - 20 mA control
current signal and causes an actuation function. There are many types of
HART actuators; a positioner is type of actuator. A device of type Actuator
can not be connected to a circuit intended for a device of type Transmitter.
An algorithm is a procedure or formula for solving a problem. There are several
algorithms entailed in SVI II AP operation. The SVI II AP has a position
control algorithm that is a modified PID. Other algorithms embedded in SVI II
AP include the STOPS method for calibrating stroke, and the autoTUNE
method for establishing the best parameters for the PID algorithm.
The combination of a single acting actuator and the control valve where the
valve is closed when air pressure is applied to the actuator.
The combination of a single acting actuator and the control valve where the
valve is open when air pressure is applied to the actuator.
A mode of the positioner in which you can change the calibration of stroke,
input signal, and tuning parameters.
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