S7 1200 down counter help!!!

[npalavras]

Hi to all, i am newbie on plc.
I would like to make a down counter with preset value 3.
Counter from 3 must goes to 2 after 2min, from 2 to 1 after 1min, finaly from 1 to 0 after 40 min.
i also would like to have the choice to pause the time from 1 to zero.
Is easy to make it with s7 1200? Please help!!!

 

[Homer_BL]

You sholud use timers instead of counters.
Define 3 timers, input preset values.
Timer 3 is enabled when process is started.
Timer 2 is enabled if timer 3 has elapsed.
Timer 1 is enabled if timer 2 has elapsed.
Process is finished if timer 1 has elapsed.
On external input timer 1 is bypassed.

 

[balash]

Hi to all, i am newbie on plc.
i also would like to have the choice to pause the time from 1 to zero.

for this Timer 1 in example should be retentive (TONR) with input buton for pause something like in att:

please bear in mind this is a sketch in paint...

EDIT:

YAY, please DO NOT FORGET TO RESET TONR after (conncet the R input to TIM1.Q) !!!

 

[npalavras]

Thank you very much for your quick replies, was very helpfull. But now with timers i face two problems:

1. what about if i wish to skip a timer with a button???
2. if i would like to represent the timer which is active on hmi. For example i will be on timer 3, τηε number 3 should appear on hmi, then the number 2 and finaly the 1????

 

[Homer_BL]

In my example you can see how to skip a timer with a button pressed.
To display status at HMI screen, do like this:
Make M3.0 active when ProcesIsON and TIM3.Q in NOT active. Then use M3.0 as VISIBILITY property of TIM3 symbol.
Make M3.1 active when procesIsOn and TIM3.Q is active and TIM2.Q is NOT active. Then use M3.1 as VISIBILITY property of TIM2 symbol etc.