Posted 13 Feb 2020 i have a third party OPC server transmitting data to 1756-L73-A17 to controller derived tags that i have created in the PLC. all of these tags are working great and retriveving the raw data from the OPC. i have one tag Titled CNA_Last_Measurement_Date_Time, this raw data transmits in the form as the raw data of 43865.7090393519, but i need it to be displayed as 02/10/2020 07:05:39. i have researched all over to find a way to do this either in the PLC or on the HMI and have not found a way to convert the Datevalue numer to a date time format. this tag changes/updates based on the last CNA measurement that was taken. does any one have a way to accomplish this via the PLC or The HMI? Share this post Link to post Share on other sites
Posted 14 Feb 2020 I'm assuming this is a real value and is a time format starting from 1900 excel uses this same thing put that number in excel reformat to time with date and you get your number so start doing a little math 43865.7090393519 43865 days from 1900 .7090393519 of the current day so 24*.7090393519=17.0169444456 so then 17 hours into the day then keep going with now the decimal left is what part of the hour is left when your done you should get 2/4/20 5:01 PM Dont forget about leap years this could get interesting 1 person likes this Share this post Link to post Share on other sites
Posted 14 Feb 2020 well, you need to know what exact calendar is used.... Gregorian, Julian or something else. roughly: day=value MOD 365.25 // account for leap year year = 1900 + (value-day)*365.25 // returns 2020 month=1 if day>31 then // exceeds January? month - month+1 day = day = 31) endif etc. Share this post Link to post Share on other sites