S7-300?

On S7-1200/1500, the Date and Time is DTL datatype, and from DTL, you can use the structure to pull out the details inside with ease. 

krzych_s

I need to convert Date_and_Time to Int

I have:

VAR

Date1 : DATE_AND_TIME

day1 : Int

In old Step7 it was simply:

day1 := DT_DAY(Date1); //using FC7

I have problem converting it to day of week in TIA.

I have found this: https://support.industry.siemens.com/cs/document/63900229/which-functions-are-available-in-step-7-v5-5-and-in-tia-portal-for-processing-the-data-types-dt-and-dtl-?dti=0&lc=en-WW

But T_CONV does not work with DATE_AND_TIME

Hi.

Only the S7-1500 has both T_CONV instruction and DATE_AND_TIME datatype.

krzych_s

But T_CONV does not work with DATE_AND_TIME

Not true.
As  <huggy_d1>  suggested you can convert to DTL type which is a structured type making individual entries available. We are encouraged to rather use DTL going forward. The convert function will look as follows in SCL:

#myDTL := DT_TO_DTL(#myDT);

As alternative you can overlay a structure of 8 byte array with the value (#myDT) to extract the elements that make up the DATE_AND_TIME. The disadvantage is that those are then in BCD numbers.

Converting to DTL is the best option for the S7-1500.

Greetings.
w

krzych_s

It is S7 - 300. S7 - 300 has also Date_and_time and T_CONV. It has no DTL.

I have done it by converting it to date using FC6 and then used date in T_CONV to convert Date to Int. Have not tested it yet but think it should work.

Sorry, my mistake.
Would this help?

krzych_s

There is no T_CONV Date_and_time -> Int on S7 300 as you have posted on image.

First I must to convert Date_and_time to Date (FC6) and then Date -> Int (T_CONV).

Strange statement - this time I used a CPU313C when developing the pictures.
What CPU are you using exactly?

krzych_s

CPU 315-2 PN/DP Firmware V3

Added img in attachment.

In ladder I can use T_CONV with Date_and_Time to INT - very strange for me.

Hi.

.. it took me a while to figure out how the image and text come together.

You are showing in the image that the SCL is not having the same functionality as the LAD. The LAD can do what you expected, but the SCL cannot. It sure does not make sense.

Yet.. in STL you have the instruction as in LAD:

The   DT_TO_*   instruction is clear that INT is not an option.

This is one of those cases that only Siemens can provide insight. Would you making them aware of this case - please. [LINK]  Explain to Siemens Support it is functionality that is possible in Step7 V5.x which in TIA Portal STL and LAD does have but SCL does not.

Thanks you for sharing this issue with the forum - now more knows of this.
w