def timeadd(datetime1, datetime2, eod=2400.0):
    """Adds time tuple 1 to time tuple 2.
    Time values greater than eod (dflt 2400)
    are converted to days

    Big question is hr 24 day 1
    """
    date1, time1 = datetime1
    date2, time2 = datetime2
    time1 = time1 + time2
    date1 = date1 + date2
    if time1 >= eod:
        time1 %= eod
        date1 += 1
    if time1 < 0:
        time1 %= eod
        date1 -= 1
    return date1, time1
