Page 182 - Programmable Logic Controllers, Fifth Edition

Parts
L1 Inputs PROX-SW Ladder logic program
CTU
COUNT-UP COUNTER CU
Counter C5:1 DN
PROX-SW Preset 10
Accumulated 0

CTU
COUNT-UP COUNTER CU
Reset PB
Counter C5:2 DN
Preset 32767
Accumulated 0 Close box
C5:1/DN B3:0/1

C5:1
Packages RES
B3:0/1
CTU
COUNT-UP COUNTER CU
Counter C5:3 DN
Preset 300
Accumulated 0
Reset PB
C5:2
RES

C5:3
RES

Figure 8-14 Can-counting program.

TON TOFRTO CTU CTD RES

Favorites Add-On Alarms Bit Timer/Counter

Tag name
True
CTU
False Count Up CU
Package_Count
Preset 12 DN
Accum 0
Input side of rung

Package_Count
RES

Tag Name Alias For Base Tag Type Style Description
– Package_count COUNTER Decimal 12 can counter
+ Package_count.PRE DINT Decimal
+ Package_count.ACC DINT Decimal
Package_count.CU BOOL Decimal
Package_count.CD BOOL Decimal
Package_count.DN BOOL Decimal
Package_count.OV BOOL Decimal
Package_count.UN BOOL Decimal
Figure 8-15 ControlLogix counter instruction.

Programming Counters Chapter 8 163

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