You will have to start with midnight. If your off-peak rate starts before midnight at 11:00 PM, you'll have to break that into two entries. One is 12 MN to 7:00 AM (our case), then at the end add 11:00 PM to 12:00 MN
For example
Peak rate is from 2:00 PM to 9:00 PM weekdays, 3:00 PM to 7:00 PM weekends and holidays
Partial peak is from 7:00 am to 2:00 PM, and 9:00 pm to 11:00 PM weekdays except holidays.
All the rest are off-peak
Weekday Entries for the Volt:
first entry would be 12:00 MN to 7:00 AM, and tag it as off peak.
then my second entry would be 7:00 AM to 2:00 PM, tag it as mid-peak
then the third entry would be 2:00 PM to 9:00 PM, tag it as peak rate
then the fourth entry would be 9:00 PM to 11:00 PM, tag it as mid-peak
then the last entry would be 11:00 PM to 12:00 MN, tag it as off-peak
It is the same with weekend and holiday rates, where you break the off-peak rates into two entries. The peak rate is between 3:00 PM till 7:00 PM then the rest are off-peak, that is from 7:00 PM to 3:00 PM. Too bad, the Volt don't know if it's a holiday or not when the holiday falls on a weekday.
Weekend entries
first entry 12 MN to 3:00 PM, off-peak
second entry 3 PM to 7 PM, peak
third entry 7PM to 12 MN, off-peak