Koso REXA Electraulic Xpac, Инструкция по установке и эксплуатации

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REXA
Electraulic Actuators & Drives
Xpac
Installation Manual -- Version 5.1 (5/09)
X-9
X3 SETUP FEATURES
Please refer to Section 6 for a detailed explanation of REXA actuator
operation. Section 6.3 should be thoroughly understood and followed
before proceeding. In addition to the standard parameters, the D
power module redefines two parameters (Low Acceleration and Ac-
celeration Breakpoint).
A servo motor can accelerate and decelerate at phenomenal rates.
For instance, the motor will accelerate from stop to 2400 RPM in one
revolution. To take advantage of this capability,
REXA
uses Propor-
Integral (PI) control in the positioning action. As the actuator
approaches the target position, the motor will decelerate (Proportional
Action) from a maximum speed to a minimum speed and then at a
preselected point, begin accelerating (Integral Action) at a fixed rate.
Tuning of the PI parameters will provide maximum response to a
control signal change without overshoot.
The speed of the unit is equal to the Gain times the difference between
the current and target positions. Upper limits on the speed remains
the value set for High Speed and the lower limit is the value set for
Minimum Speed (Figure X.1).
Integral action utilizes the values of Acceleration Breakpoint and Low
Acceleration in the ACC Branch. The speed will increase at the value
for Low Acceleration, but will not start this increase until it reaches
the Acceleration Breakpoint.
PROPORTIONAL
Gain (dG) controls the point at which the actuator will begin to decel-
erate. Values from 5 to 200 may be selected. The higher the value,
the closer the unit will be to the target position before the calculated
motor speed begins to drop below High Speed. Recommended ini-
tial settings are shown in Figure X.2. The effect of this parameter on
performance is indicated in Figure X.3.
Minimum Speed (dL) specifies the lowest speed in percent of maxi-
mum that the motor will reach under proportional control. Values from
5 to 20 may be selected. Recommended initial setting are shown in
Figure X.2. The effect of this parameter on performance is indicated
in Figure X.3 .