Study on Counters and Timers | Assignment

1
Counters and Timers
Name
Institutional Affiliation
Counters and Timers.

2
TON timer is a timer used in delaying turning an output ON. The out bit of the
timer turns ON after the timer has completed running. When pre-set value is
loaded into existing value the 1st time the timer is scanning the program. When the
timer’s input conditions rises, the timer starts to decrease and when the existing
value reaches zero, while input conditions is ON, the out bit turns ON. When
input conditions falls, preset value is loaded to current value.
TOF timer is a timer used in delaying an output OFF. The out bit of the timer
turns OFF after the timer has completed running. When the timers input
conditions increases, the out bit of the timer turns ON and loads the pre-set value
to current value. Falling in the input condition of the timer, the timer starts to
decrease, out bit of the timer remains ON as the timer is running and when
current value equals TO zero ,bit out of the timer turns OFF. If input conditions
of the timer increases while the timer is decreasing, out bit of the timer remains
ON and time stops operating (Money, 2014).
RTO timer is a timer that counts interval of time when the instruction feed is true
and holds the accumulated value. Incase power cycles arises or the instruction
becomes false, the program starts to count the base time interval and the
operational conditions becomes true.
CTU counter is a PLC counter that is used in counting upwards. Individual pulse
on the count input increases the CV of the counter by one. In case the CV
becomes ≥counter limit then output value is set. The reset input pulse resets the
current counter value to zero (Godse, 2009).