Omron C200H-MC221 -, Руководство по эксплуатации

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Glossary
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CPU Backplane A Backplane used to create a CPU Rack.
CPU Rack The main Rack in a building-block PC, the CPU Rack contains the CPU, a Power
Supply, and other Units. The CPU Rack, along with the Expansion CPU Rack,
provides both an I/O bus and a CPU bus.
CW and CCW Abbreviations for clockwise (CW) and counterclockwise (CCW). CW and CCW
are defined for a motor shaft in reference to a viewer facing the shaft on the end
of the motor from which the shaft extends from the motor for connection.
CW/CCW limits Limits on the CW and CCW sides of the origin which can be internally set to
restrict rotation of the shaft.
data area An area in the PC’s memory that is designed to hold a specific type of data.
decimal A number system where numbers are expressed to the base 10. In a PC all data
is ultimately stored in binary form, four binary bits are often used to represent
one decimal digit, via a system called binary-coded decimal.
DM Area A data area used to hold only word data. Words in the DM area cannot be
accessed bit by bit.
dwell time A setting that specifies the period of time during which positioning will stop
before execution of the next positioning action.
error counter A counter used to ensure positioning accuracy when positioning via pulse trains.
The error counter receives a target position as a specific number of pulses in a
pulse train from the Motion Control Unit and outputs analog speed voltages to
drive a servomotor accordingly. The specified number of pulses in the error
counter is counted down by feedback from an encoder measuring actual motor
shaft movement, causing voltage output to stop when the number of pulses
equals zero, i.e., when the target position has been reached.
feedback The return of a portion of the output of a circuit or device to its input. It is used in
servocontrol systems to help bring actual values closer to target values.
flag A dedicated bit in memory that is set by the system to indicate some type of oper-
ating status. Some flags, such as the carry flag, can also be set by the operator
or via the program.
gain The increase in signal power produced by an amplifier.
G language A programming language used widely in position control. Program functions are
entered simply by entering a “G,” a 2-digit numerical code, and adding any
needed parameters.
hunting The tendency, in servosystems, to overcompensate when the system’s momen-
tum carries it past the target position.
IBM PC/AT or compatible A computer that has similar architecture to, that is logically compatible with, and
that can run software designed for an IBM PC/AT computer.
inching Manual feeding wherein positioning is executed one pulse at a time.
incremental position A position given in respect to the present position, rather than in respect to the
origin.
initial position The present position when a start command is executed.