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

Page 162

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Special Programming Techniques

Chapter 11

11Ć15

Figure 11.8

24 Hour Clock

030

15

030

1.0

TON

Rung 1

PR 060

AC 000

030

15

031

CTU

Rung 2

PR 060

AC 000

031

15

032

CTU

Rung 3

PR 024

AC 000

031

15

031

CTR

Rung 4

PR 060

AC 000

032

15

032

CTR

Rung 5

PR 024

AC 000

Seconds

Minutes

Hours

Resets

the clock

A synopsis of the operation’s cycle is:

Rung 1: When the conditions are true the timer will start.

Rung 2: When AC=PR (accumulated value equals preset value) of the timer,
counter 031 increments.

Rung 3: When AC=PR of counter 031, counter 032 increments.

Rung 4: When AC=PR of counter 031, the -

031

(CTR)

- resets counter 031’s

accumulated value.

Rung 5: When AC=PR of counter 032, the -

032

(CTR)

- resets counter 032’s

accumulated value.