TM919TK Astronomical Timer Key benefits Automatic sunrise/sunset adjustment: The TM919TK calculates local sunrise and sunset times from your entered coordinates and automatically adjusts switching times throughout the year, eliminating daily manual changes. Reliable, longterm calendar: Builtin calendar valid from 2017 through 2042 ensures accurate date handling without firmware updates for years. Precise geographic configuration: Set exact location and time settings so the timer responds correctly where you install it. What it does and why you need it Keeps lights and systems synchronized with natural daylight: ideal for saving energy, improving security, and maintaining consistent schedules for lighting, signage, or climate/plant lighting systems. Reduces maintenance: once latitude, longitude, and time zone are set, the timer adapts automatically to seasonal light changes. Improves accuracy and local relevance: using your precise latitude and longitude means the device calculates onsite sunrise/sunset rather than relying on generic offsets. Key specifications and compatibility Model: TM919TK Latitude range: 0 to 70 degrees North (suitable for locations between the equator and 70° N) Longitude range: 180 to 180 degrees Time zone range: +12 to 12 (covers global time zones; can be set for eastern and western hemispheres) Builtin calendar: valid from 2017 to 2042 Function: automatic astronomical calculation of sunrise/sunset with userconfigurable geographic and time zone settings Performance and reliability Automatic calculations provide consistent switching tied to actual daylight times. Designed for yearround operation without daily manual adjustments. Clear parameter ranges let you confirm compatibility before installation. Practical use scenarios Outdoor and landscape lighting: Program lights to turn on at local sunset and off at local sunrise, adapting automatically through seasons to maintain consistent nighttime illumination. Security and commercial signage: Keep signage and security exterior lights synced to actual daylight hours to enhance visibility and safety while minimizing energy waste. Greenhouse or aquarium lighting: Schedule grow or photoperiod lights to follow natural sunrise/sunset cycles appropriate for your latitude, supporting plant or animal needs without daily manual changes. Setup considerations Enter your location using latitude (0–70° N) and longitude (180 to 180) and select the appropriate time zone (+12 to 12) during initial setup. Confirm the builtin calendar range (2017–2042) meets your deployment timeframe. The TM919TK provides automated, locationaccurate control of devices tied to daylight, reducing manual work and ensuring consistent operation across seasons.