I have two string measure values (Login Time) which i want to add it in the Table. I have added the same in rows but i am unable to get the Total for that. Why string time format ? Because while converting total time to HH:MM:SS it was showing wrong values because Tableau doesn't have that feature to show Time more than 24 Hours format so i have done the calculation where it is converted into string values. Now how to show Total or can someone help to convert time into 24 hrs without string ?

Calculations to derive correct time  beyond 24 hours as mentioned below -

STR(INT(SUM([Voice Login Time])/3600))+ ":" +

IF INT(SUM([Voice Login Time]) %3600/60)

<10 THEN "0" ELSE "" END +

STR(INT(SUM([Voice Login Time]) %3600/60)) + ":" +

IF INT(SUM([Voice Login Time]) %3600 %60)

<10 THEN "0" ELSE "" END +

STR(INT(SUM([Voice Login Time])%3600 %60))

Hence the above measure converted to string which i want to add it in the table with total for all the employees. Please help!