Intermatic ST01K Astronomic Digital In-Wall Timer - Reliable Auto

Our review of the Intermatic ST01K finds it best suited for homeowners and electricians who want a simple, dependable timer that handles modern lighting without rewiring. The single biggest reason to buy is its combination of an astronomic sunrise/sunset feature and a no-neutral design, which makes it ideal for retrofits where pulling a neutral is impractical. Installation is straightforward for single-pole or 3-way circuits, and once programmed the unit largely manages itself thanks to automatic daylight saving adjustment and battery backup.

Key Features

• Astronomic scheduling: Automatically adjusts on/off times to local sunrise and sunset so outdoor or entry lighting follows seasonal changes without manual edits.
• 24-hour or 7-day modes: Lets users choose daily or weekly programming for different occupancy patterns and weekly routines.
• Up to 20 events: Stores multiple on/off events to accommodate complex schedules like varied evening and early-morning scenes.
• No neutral required: Designed for retrofit and remodel projects where a neutral conductor is not available, saving time and wiring work.
• LED and CFL compatible: Controls modern lighting types along with incandescent loads so it works with common lamp and fixture types.
• Random and backup: Randomized on times provide a lived-in look when away, and battery backup preserves schedules during power interruptions.

Who It's For

The ST01K is excellent for homeowners upgrading hall, porch, or exterior lighting who need an automatic solution without running a neutral wire, and for electricians doing remodels where access to neutral is limited. Its astronomic feature is particularly useful for properties where sunset/sunrise timing changes are important for security or convenience.

Less suitable users include those who want Wi-Fi or smartphone control, or installers needing networked home automation integration; this is a reliable, standalone timer rather than a smart home hub component.

Pros & Cons

Pros

• Reliable astronomic scheduling eliminates daily manual changes for sunrise/sunset times.
• No neutral requirement simplifies retrofits and reduces installation time in older homes.
• Compatible with LED, CFL and incandescent loads so it handles modern bulbs reliably.
• Battery backup and a large LCD make programming and status checks easy and robust.

Cons

• Does not provide Wi-Fi or app control, so remote operation is not available.
• Requires a decorator style wall plate sold separately, adding a small extra purchase.

Specifications

Brand	Intermatic
Model	ST01K
Timer modes	24-hour or 7-day digital
Events	Up to 20 ON/OFF events
Astronomic feature	Yes (sunrise/sunset adjustment)
Neutral wire	No neutral required
Applications	Single-pole and 3-way

Our Verdict

The Intermatic ST01K is a practical, no-nonsense in-wall timer for anyone needing automatic sunrise/sunset control without rewiring for a neutral. It offers strong value for retrofit projects and basic timed lighting needs, delivering dependable scheduling, battery backup and broad bulb compatibility without the complexity of smart home platforms.

Frequently Asked Questions

Can this timer control LED and CFL lights?
Yes. The ST01K is compatible with LED, CFL and incandescent lighting types.

Does it need a neutral wire to install?
No. The design specifically does not require a neutral, making it suitable for retrofit and remodel installations.

Will it adjust for daylight saving time?
Yes. The unit includes automatic daylight saving time adjustment and an astronomic feature for sunrise/sunset changes.