In the previous lessons you learned that when you want to use SIMATIC timers in your PLC programs you need to assign the time value as S5TIME format. For instance, if you want this timer here to time for 10 milliseconds, you need to enter S5T#10ms as the time value for the timer. But in some projects, you need to assign a variable as the time value instead of a fixed amount. For instance you can assign a memory address like MW0 as the time value for the timer. By doing this, any value that you assign to this address will be considered as the time value for the timer. So here the timer can have different time values depending on the value that you enter for this address.