Owner's manual
Menu 6: Parameter for Position Controller
Along with thedetermination of theactuatorgeometry and control
parameters the suitable setting parameters forthe position controller are
determined via function AUTO- STARTinMenu2.Assessmentofa
control behavior generallyisvery subjective.Partiallyaquickresponseis
requested withoutconsiderationofthe overshootwidth, partiallyavery
smoothswinging is requested with minor overshoot.
We basically recommend to first performthe execution of theautomatic
setting via AUTOSTART in Menu 2inorder to achieve a stable control
behavior. Corrections maythenbemadefromthe determined values.
In rare cases AUTOSTART cannot find theoptimal setting forthe
respective application.See “Remarks forcontroller optimization” following
table 4.
For small actuators an improvement of thecontrol behaviorcan be achie-
ved also by increasing damping at the pneumatic output. Afurther
optimizationmay follow by repeatingAUTOSTART.
M 1234
½½ -½-M, LED 1and LED3flash
Seven controlparametersare combined in Menu 6each availing of asub-
menu. 15 different values maybeselectedineachoftheseand pressing
of (
)be enteredinthe positioncontroller as constant.Controller type is a
PI controller.
Parameter-
Designation
Valveis
opening
Valve is
closing
Unit
Proportionate
amplification
KP
P P -
Integration time
constant
Tn
Tn sec
Positioning time
T63
T63 sec
Dead band for
control diff.
GAPGAP %of span
The dead band prevents(at theexpense of accuracy) that the valve in the
controlled condition constantly moves around the setpoint. This lessharms
themechanical partsofthe actuator andinparticular thevalve packing.
Selectionofsub-menus:
M 1234
¼-¾- -M,LED2flash: P
¼¾¾ --M, LED 1and LED2flash: P
¼- -¾-M,LED3flash:Tn
¼¾ -¾-M, LED 1and LED3flash: Tn
¼ ---¾M,LED4flash:T63
¼¾ --¾M, LED 1and LED4flash: T63
¼-¾¾ -M, LED 2and LED3flash: GAP
Followingselection of thesub-menu thecodesfor the parameter values
(table 4) can be selected by pressing (
):
SRD Main Menu
4 Valve Char.
5 Limits/Alarms
6 Parameters
6 Parameters
6.1 Gain closing
6.2 Gain opening
6.3 Res time cl
etc.
6 Parameters
6.4 Res time op
6.5 Rate lim cl
6.6 Rate lim op
6 Parameters
6.5 Rate lim cl
6.6 Rate lim op
6.7 Control gap
Page 46
Startup
August 2014POS-UM-00009-EN-02