Rockwell Automation 1772-LV Mini-PLC - 2/15 Programmable Controller (Series B) Programming and Operations - Manual (Page 204)

Glossary
Appendix B
BĆ11
Module
An interchangeable “plug-in” item containing electronic components which
may be combined with other interchangeable items to form a complete unit.
Module Group
Adjacent I/O modules which relate 16 I/O terminals to a single 16-bit image
table word. A Mini-PLC-2 module grouping contains 2 modules, each with 8
I/O terminals.
Monitor
1) CRT display package. 2) To observe an operation.
Non-Retentive Output
An output which is continuously controlled by a single program rung.
Whenever the rung changes state (true or false), the output turns on or off.
(Contrasted with a retentive output which remains in its last state (on or off)
depending on which of its two rungs, latch or unlatch, was last true.)
Non-Volatile Memory
A memory that is designed to retain its information while its power supply is
turned off without requiring a backup power source.
Octal Numbering System
One which uses a base eight, e.g., the decimal number 324 would be written in
octal notation as 5048. Only the digits 0 thru 7 are used.
Off-Delay Timer
1) In relay-panel application, a device in which the timing period is initiated
upon de-energization of its coil. 2) In PC, an instruction which turns off one or
more outputs (by means of other rungs) after a programmed time delay. While
the preconditions of the off-delay timer rung are true, the outputs are energized.
Whenever the rung goes false, the time delay is started, and the outputs are
de-energized at its completion.
On-Delay Timer
1) In relay panel applications, a device in which the timing period is initiated
upon energization of its coil. 2) In PC, an instruction which turns on one or
more outputs (by means of other rungs) after a programmed time delay. While
the preconditions of the on-delay timer rung are false, the outputs are
de-energized. whenever the rung goes true the time delay is started, and the
outputs are energized at its completion.
On-Line Data Change
This feature allows the user to change various data table values through the
program panel while the application is operating normally.
On-Line Operation
Operations where the programmable controller is directly controlling the
machine or process.