Koso REXA Electraulic Xpac, Installation And Operation Manual

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REXA
Electraulic Actuators & Drives
Xpac
Installation Manual -- Version 5.1 (5/08)
29
6 OPERATION
There are three modes in which the actuator operates; Auto, LOCAL
and SEtUP . As long as power is applied, the actuator will be in one
of these modes. If power is removed and later restored, the actuator
will resume operation in the last active mode. In the
Auto mode, the
actuator responds to the control signal by automatically adjusting its
position to match the control signal's target position. The
LOCAL
mode provides a means of manually adjusting the actuator's position.
The
SEtUP mode is used to calibrate the actuator to the application
and to set operating parameters which govern the dynamics of actua-
tor movement. Each mode is entered by simultaneously pressing and
releasing two keys of the three button keypad:
To enter Auto mode, press (E)NTER and Scroll Down.
To enter LOCAL mode, press (E)NTER and Scroll Up .
To enter SEtUP mode, press Scroll Up and Scroll Down.
When a mode change is invoked, the actuator responds by briefly
displaying the requested mode.
Two additional references are available to guide the user through
the operation and calibration of an
Xpac.
They are the Operating
Parameter Sheet affixed to the cover of the Control Enclosure and
the Setup Quick Reference contained in the Appendix. After a basic
understanding of the operation is gained, these two simple and straight
forward sources should answer most questions.
6.1 Auto Mode
In the
Auto
mode, the actuator tracks the control signal. The actua-
tor may be configured to operate with either an analog loop (usually
4-20 mA) or it may be driven by a pair of pulse signals. The control
signal is continuously sampled and converted to an equivalent target
position in terms of the actuator's calibrated stroke. When necessary,
the actuator adjusts its position to match the target position.
The
Auto
mode is distinguishable from the other modes by its display.
The actuator's current position, in percent of calibrated stroke, is dis-
played in the three right most digits. The left two digits are blank.
While converting the control signal and adjusting its position, the
PCP monitors the operation of the actuator. If an error condition is
detected, the display alternates between position and an identifying
error code (see Section 8).
While in the
Auto mode, setup parameters may be reviewed without
taking the unit "off-line." The Scroll Up and Scroll Down buttons
POSITION