User manual

Publication 1763-UM001E-EN-P - March 2015
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relay logic
A representation of the program or other logic in a form normally used for
relays.
restore
To download (transfer) a program from a personal computer to a controller.
reserved bit
A status file location that the user should not read or write to.
retentive data
Information associated with data files (timers, counters, inputs, and outputs) in
a program that is preserved through power cycles.
RS-232
An EIA standard that specifies electrical, mechanical, and functional
characteristics for serial binary communication circuits. A single-ended serial
communication interface.
run mode
This is an executing mode during which the controller scans or executes the
ladder program, monitors input devices, energizes output devices, and acts on
enabled I/O forces.
rung
Ladder logic is comprised of a set of rungs. A rung contains input and output
instructions. During Run mode, the inputs on a rung are evaluated to be true
or false. If a path of true logic exists, the outputs are made true. If all paths are
false, the outputs are made false.
save
To upload (transfer) a program stored in memory from a controller to a
personal computer; OR to save a program to a computer hard disk.
scan time
The time required for the controller to execute the instructions in the
program. The scan time may vary depending on the instructions and each
instruction’s status during the scan.