Rockwell Automation AutoMax Enhanced Ladder Language Reference Manual - Manual (Page 35)

2Ć1
2.0 Counter Instruction
Use counter instruction (CTUD) to count activities as they occur, like products passing
over a switch on a conveyor belt or pushes of a button. The counter instruction uses the
counter data type to control the counter instruction.
The value in Current can count up past the preset value and down past zero. However,
the value in Current cannot exceed the upper limit or go below the lower limit of a
double integer.
The QU and QD outputs do not change state unless the instruction is executed, even if
the CPreset has been modified to be less than or equal to the current value.
I
MPORTANT
Global counters must be entered into the variable configurator as fiveĆelement,
doubleĆinteger, nonĆvolatile arrays.
Example: COUNTER1!(4).