Hello,

I need to perform the subtraction between two times of different days in hours.

(I am using a S71500 / TIA Portal V17)

The idea is to use the current day and time LESS the day and time of the beginning of a process.  The result of this subtraction should be hours.

Example:
1st 10:00 am 07/28/2023
2nd 10:00 am 07/31/2023.

The result (1st - 2nd) should be 72 hours.

I'm trying to use some TIA instructions but without success so far.

Regards
Fernando​

Hello FerroFernando;

You might be iterested on his FAQ on manipulating Time variales, especally in the T_Sub instruction available for S7-1200 and S7-1500 CPUs:

https://support.industry.siemens.com/cs/ca/en/view/63900229

Look up T_Sub in the online help of your Step 7 software.

Hope this helps,

Daniel Chartier