Entry type: FAQ, Entry ID: 67585220, Entry date: 02/28/2013

How do you declare the timers and counters for the S7-1500 in STEP 7 (TIA Portal)?

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  • Associated product(s)
Using timers and counters in STEP 7 V5.x and in STEP 7 (TIA Portal).

In this entry we deal with the topic of "Using times in the program" and the different ways of proceeding in STEP 7 V5.x and STEP 7 (TIA Portal).

Procedure in STEP 7 V5.x
Due to their compatibility with STEP 5 you can also use STEP 7 S5 Timer and S5 Counter. These timers/counters are global and are addressed by one number. When you start the timers/counters, with the call of the "Value Range" and "Precision" modes it is defined whether the timer is to run as switch-on delay or the counter as up counter. Pay attention to the following system properties when calling and setting parameters:

  • The programs are specifically number-dependent.
  • Blocks with S5 timers/counters cannot be used multiple times.
  • The value range of the time is limited to a maximum of 9990s and that of the counter to a maximum of 999.
  • The interval times are 0.01 .. 9.99, 0.1 … 99.9, 1 … 999 and 10 … 9990 seconds.
  • The timer precision depends on the time interval selected.

Procedure in STEP 7 (TIA Portal)
Declare the timers and the counters in the block in which they will be called and used. The IEC time is a structure of the data type IEC_TIMER, IEC_LTIMER, TON_TIME or TON_LTIME, which you can also declare as local variable in a block.


  • You can call the block multiple times with newly created instance data blocks.
  • The blocks have a wider counting range and the timer precision is independent of the interval timing.
  • The IEC timer provides a better performance than the S5 timers.

Fig. 01 shows two examples for this procedure. The IEC time "SwitchDelay" was declared as local variable of the data type "TON_TIME" and the IEC counter "CountDB" as local variable of the data type "CTU_INT".

Fig. 01

Creation environment
The figures in this FAQ response were created with STEP 7 (TIA Portal) V12.