TL;DR
A transformer tap is one of the multiple output terminals on a low-voltage landscape lighting transformer, commonly labeled 12 through 15 volts, used to compensate for the voltage lost along long wire runs. A fixture far from the transformer might receive only 9 volts off the 12-volt terminal, so the installer lands that run on the 14-volt terminal to deliver the proper voltage at the fixture, verified with a meter at the farthest lamp.
What it means
A transformer tap is one of the multiple output terminals on a low-voltage landscape lighting transformer, commonly labeled 12 through 15 volts, used to compensate for the voltage lost along long wire runs. A fixture far from the transformer might receive only 9 volts off the 12-volt terminal, so the installer lands that run on the 14-volt terminal to deliver the proper voltage at the fixture, verified with a meter at the farthest lamp. Halogen systems depended on this heavily; LED fixtures with wide input ranges have made tap choice more forgiving but not irrelevant.
Where it sits in the glossary
Transformer tap 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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