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2 output instructions – Rockwell Automation 1772-LP3 PLC - 2/30 Programmable Controller Programming and Operations Manual User Manual

Page 69

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Introduction to Programming

Chapter 4

4Ć5

Figure 4.5

Examine Off Instruction

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05

(ą)

14

112 012

The output instructions set an addressed memory bit to one (on) or reset it
to zero (off). An output image table bit, as one or zero, can cause an output
device to be turned on or off.

Output instructions are programmed at the end of the ladder-diagram rungs
(Figure 4.3). Only one output instruction can be programmed on each rung.
An instruction in this position of the rung is executed only if the rung
conditions preceding the instruction are logically true.

These output instructions are:

Output Energize –( )–
Output Latch –(L)–
Output Unlatch –(U)–

These instructions are used to set memory bits on or off in any area of the
data table, excluding the processor work areas and the input image table.

Output Energize Instruction

The Output Energize instruction tells the processor to turn an addressed
memory bit on when rung conditions are true. This memory bit may
determine the on or off status of an output device. This instruction can also
be used to set a storage bit to one for later use in the program. It also turns
the bit off when the rung conditions go false.

The Output Energize instruction tells the processor to turn the addressed
memory bit off when rung conditions go false (Figure 4.6).

4.3.2
Output Instructions