How to format converted Time from Oracle 8i (seconds) to Time XX:XXpm

[KKUB]

I am attempting to reformat the time in an Oracle database which is currently in Seconds to a standard 12 hour clock time.I successfully convert secondes into two field with correct 24 hour clock Hrs and Min.
Example "Hrs= 6", "Min = 0"
I used StrTotaltime: Format([HRS] & [Min],"nn:nn") the desired result should be "06:00