TL;DR
An astronomical timer is a lighting control that computes sunrise and sunset daily from the installation's latitude, longitude, and date, switching outdoor lights without the photocell that ordinary timers need to track the seasons. Once programmed with location and time, it shifts on/off times automatically through the year and can offset them, such as on at sunset, off at midnight.
What it means
An astronomical timer is a lighting control that computes sunrise and sunset daily from the installation's latitude, longitude, and date, switching outdoor lights without the photocell that ordinary timers need to track the seasons. Once programmed with location and time, it shifts on/off times automatically through the year and can offset them, such as on at sunset, off at midnight. Versions range from in-wall switches to transformer-mounted modules in low-voltage landscape systems. It eliminates the failure modes of photocells, which stick, age, and false-trigger from headlights or snow.
Where it sits in the glossary
Astronomical timer is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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