Koso REXA Electraulic Xpac, Installation And Operation Manual

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Xpac
Installation Manual -- Version 5.1 (5/98)
R-4
REXA
Electraulic Actuators & Drives
Wiring is accomplished as two separate units. A Power Module and feedback
circuit is connected to a single electronics. Please refer to Section 5 for a
single B or single C connection and to Appendix X for a single D connection.
R.2.1 User Connections
Electrical power and control signal are wired in the conventional manner
(Section 5.3). However, consideration should be given to maintaining the
redundancy down to these user connections. Power should be brought
from two sources. A single control signal looped through both electronics
is possible, but two independent signals can be connected.
R.2.2 Redundant Interconnections
Each PCP has two auxiliary board I/O ports, upper and lower. The upper
port is used to install the auxiliary boards required for redundant operation.
The determination of main and backup is dependent only on these boards.
The main power module would utilize the alarm board p/n S96169 and the
backup will utilize status board p/n S96584. Exchanging the two different
boards and operating software will reverse the main and backup modules.
Other auxiliary boards are installed on the lower port and connected in the
conventional manner per Appendix C.
R.2.2.1 Alarm Indication
The alarm relay is used to indicate the online status of the main Power
Module. Power for the alarm is obtained from the main actuator power.
Interconnection wiring between the Status Boards and second module is
shown in Figure R.2 (p. 5).
R.3 Operation
The operation (Section 6) is substantially unchanged from a standard unit.
However, some mention should be made to the interaction of two independent
Power Modules on the same cylinder. Both PCPs are looking at the actual
position and comparing this to the target position set by the control signal.
If the target position for one module is satisfied, but not for the other, then
one module will reposition the actuator. If the repositioning causes the first
module to move outside of its target, then it will move the actuator back.
This action would occur with the same signal and low deadband settings (<
0.5%). Such operation is alleviated by simultaneous SEtUP and the backup
unit’s deadband having an internal setting eight times that of the main unit.
Another extraordinary condition will happen if one module is put into LOCAL
and moved manually. The other unit will continue to track the control signal
and move the actuator back. Placing both PCPs in LOCAL and moving only
one remedies this situation.
User connections should
only be made to auxiliary
boards on the lower port.