Rockwell Automation 1772-LS_LSP,D17726.8.6 PROG/OPER MANUAL-MINI PLC-2/05 User Manual

Page 59

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Relay-type Instructions

Chapter 6

6Ć7

Here two conditions are parallel. As long as one of the conditions (C1 or C2) is
true, a continuous path to the action exists. Therefore, the action is performed.

True

True

C3

C1

A

False

True

C4

C2

Here are two sets of parallel conditions. If either set of conditions are true, the
action is performed.

010

00

010

00

110

10

110

12

This illustration shows a program rung with branching, as it would appear by
the 1770-T3 terminal display. You create a branch by using two different
branch instructions. These are the branch start and branch end instructions.

Branch Start/End
Purpose: A Branch Start instruction begins each parallel logic branch of a rung.
It allows more than one combination of input conditions to energize an
output device.

A Branch End instruction completes a set of parallel branches.

Keystrokes: You enter a Branch Start or Branch End instruction by performing
the following steps

1.

Press either [

] or [

].

Important: You must begin each rung of parallel conditions with a Branch
Start instruction.

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