Technical Specifications

563
Mode
Wizard Step 4
When selected, you can perform an Auto Tune. The SVI positioner is a PID servo control
device with special parameters unique to valve positioners. Because the SVI can be put on a
wide variety of valves, the values of the parameters must be changed to match each valve.
The SVI can determine a good set of parameters automatically. When the Auto Tune
procedure is run, the SVI performs a series of open and closed loop tests to determine
values for P, I, D, Padj, Beta, Position Compensation, and DeadZone.
The values determined should give good general operation of the valve, however these
values are determined by a target set of performance criteria built into the SVI. You may
want performance different than this set and may therefore want to set the PID values
differently than determined by Auto Tune. This can be done on the “Calibrate Tab” on
page 581.
Wizard Step 5
Click and when Setup Wizard completes a report of settings appears using the selection
made in Report Setup.
Mode
The SVI can be in any of several operating modes:
Operating In this mode the SVI responds to the input signal and positions the
valve appropriately (indicator green).
Manual In this mode the valve does not respond to the input signal. Instead
it remains stable in one position which is the position that the valve
was when manual mode was entered or a new position selected
by the user (see Setpoint) (indicator yellow).
Configure In this mode you can set configuration parameters of the posi-
tioner or controller (indicator yellow).
Calibrate In this mode you can set calibration parameters of the positioner
(indicator yellow).
Diagnostic In this mode you can run response time tests, step response tests,
and positioner signatures (indicator yellow).
Bumpless transfer This is a transition mode when you select operating mode from
manual mode (see Bumpless Transfer) (indicator red).