Koso REXA Electraulic Xpac, Инструкция по установке и эксплуатации

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Xpac
Installation Manual -- Version 5.1 (5/09)
C-12
REXA
Electraulic Actuators & Drives
Speed Breakpoint (Sb) specifies the transition point, in percent of
stroke, from Low Speed to High Speed . Operation of the actuator at
strokes below the Speed Breakpoint will be at the Low Speed setting.
Operation of the actuator at strokes above the Speed Breakpoint
will be at the High Speed setting. The actuator will accelerate and
de-accelerate, as appropriate, when the motion causes the actual
position to cross the Speed Breakpoint.
Speed Breakpoint may be set to any value between 0.0% and 100%.
Setting Speed Breakpoint to 0.0% will cause the actuator to always
use the value set in High Speed. Setting Speed Breakpoint to 100%
will cause the actuator to always use the value set in Low Speed.
C.6.4 Flow Characterization
The Xpac is designed to have an inherent linear relationship between
Control Signal and stroke (10% CS, 10% stroke, etc.) The ability
to modify this characteristic can assist in loop tuning or linearizing
a control scheme. Changing the
Xpac
’s characteristic can have a
profound effect on the behavior of the control loop and should only
be undertaken with a thorough understanding of the effect.
An 11 point, 10 line segment characterization provides the ability to
simulate most common control curves or to linearize the actuator
to within .05%. The stroke position can be modified at 10% control
signal intervals. The only restriction is that each stroke position
must be at least 2.5% from its neighbors.
FCH - FLOW CHARACTERISTIC SUB-MENU
Flow Characteristic (FC) activates the characterization scheme. If
this parameter is ON, then the position values in parameters C1 . .
. C9 are followed. If this parameter is OFF, then the inherent linear
curve is followed.
C1 through C9 denotes the actuator’s position at 10% control signal
(CS) intervals. C1 is the actuator’s position at 10% CS, C2 is the
actuator’s position at 20% CS, C9 is the actuator’s position at 90%
CS. The endpoints are still defined by the values of Position Low
(PL) and Position High (PH) in the CAL sub-menu.
TUNING
Before any attempt at modifying the flow characteristic is made,
both a graphical representation and table of the values should be
developed. Figure C.A shows typical inherent flow characteristics
for the major valve styles and a table to convert these curves into
inherent linear characteristics.
C.S. 10% POINT
C.S. 20% POINT
FLOW CHARACTERISTICS
SPEED BREAKPOINT
C.S. 90% POINT