The PLC counter output goes on after the set count is received by repetitive pulses to the counter input.
Straight counting in a process
After a certain number of counts occur, the output goes on.
The output can be used to energize an indicator.
The output status could also be utilized in the ladder diagram logic in the form of a contact.
Either counter will function (count) if its input rung transitions from false-to-true.
After the count input receives 18 pulses, the O:2/0 output will energize.