OPC Tag Value Seconds to HH:MM:SS via Expression Tag

Not an expression, but another option would be to do this in a script library:

from java.util import Locale
from com.inductiveautomation.ignition.common import FormatUtil

def formatTime(time):
	return FormatUtil.formatDuration(Locale.getDefault(), time, FormatUtil.DurationFormatStyle.COMPACT, False)
>>> formatTime(1123311123)
u'13d 00:01:51'
>>> formatTime(1123311)
u'00:18:43'
>>> formatTime(38460)
u'00:00:38'
>>> formatTime(38460123)
u'10:41:00'
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