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How Do I Perform a Factory Reset and Complete Initial Setup on an Older ST01 or EI600 Timer (Pre 2023)?

Applies To

ST01 and EI600 Series in-wall timers (older versions with NOR, CENT and SOU Astronomic zone selection)

Note: Older ST01 and EI600 timers use a three-zone Astronomic system to determine your approximate latitude. Newer models released in February 2023 include LAT and LONG entry, language selection and an optional countdown mode. To identify your version, check the instruction sheet included with the timer. The older version is titled "ST01-EI600 Series Instructions." The newer version is titled "ST01-EI600 Series Instructions with Countdown Timer."

Question / Problem

How do I perform a factory reset and complete the initial setup on an older ST01 or EI600 timer?

Conditions

  • The setup menu includes NOR, CENT and SOU zone selection instead of LAT and LONG.
  • Initial setup must be completed before any ON or OFF events can be programmed.
  • A factory reset clears all programmed events and restores the timer to its default state.

Step-by-Step Resolution

  1. Perform a Factory Reset

    Press and hold ON/OFF. While holding it, press and hold RESET for five seconds, then release RESET. Keep holding ON/OFF until the display shows 12:00 a.m. blinking in MAN mode, then release.

  2. Enter SETUP Mode

    Press MODE until SETUP appears on the display, then press ON/OFF to begin entering the time and date.

  3. Set the Current Hour

    Use + or - to set the current hour, making sure the a.m. or p.m. indicator is correct, then press ON/OFF to confirm.

  4. Set the Current Minute

    Use + or - to set the current minute and press ON/OFF to confirm.

  5. Set the Year

    Use + or - to select the current year, then press ON/OFF to confirm.

  6. Set the Month

    Use + or - to select the current month and press ON/OFF to confirm.

  7. Set the Date

    Use + or - to select the current day of the month, then press ON/OFF to confirm. The timer displays the day of the week.

  8. Confirm the Day of the Week

    If the displayed day is correct, press ON/OFF to accept it. If not, review and correct the previous date settings.

  9. Select the Daylight Saving Time Setting

    Use + or - to choose AUTO if your area observes daylight saving time or MAN if it does not, then press ON/OFF to confirm.

  10. Select Your Astronomic Zone

    Use + or - to choose NOR (northern United States and southern Canada), CENT (central United States) or SOU (southern United States) for your approximate latitude, then press ON/OFF to confirm. Refer to the zone map in the instruction sheet included with the timer.

  11. Adjust the Dawn Offset if Needed

    The timer displays the calculated dawn time. Use + or - to adjust dawn earlier or later, then press ON/OFF to confirm.

  12. Adjust the Dusk Offset if Needed

    The timer displays the calculated dusk time. Use + or - to adjust dusk earlier or later and press ON/OFF to confirm.

  13. Exit SETUP

    After dusk is confirmed the display returns to SETUP. Press MODE to exit setup and prepare the timer for programming events.

Tips / Additional Notes

  • A factory reset is the only way to restore the timer to its original default state.
  • If you need to change only the time, date or Astronomic zone without clearing programmed events, enter SETUP mode without performing a factory reset.
  • Areas that do not observe daylight saving time include most of Arizona and Hawaii. Set DST to MAN in these locations.
  • A CR2 lithium backup battery maintains the clock and programmed schedule during power outages. Replace the battery if the timer loses its settings after a power interruption.