TL;DR
A surge protective device is a panel-mounted unit that clamps transient overvoltages from lightning, grid switching, or motor loads and diverts them to ground before they reach branch circuits. Type 1 units install at the service entrance and Type 2 at the load center, rated by clamping voltage and surge current in kiloamps.
What it means
A surge protective device is a panel-mounted unit that clamps transient overvoltages from lightning, grid switching, or motor loads and diverts them to ground before they reach branch circuits. Type 1 units install at the service entrance and Type 2 at the load center, rated by clamping voltage and surge current in kiloamps. NEC 230.67 now requires one on new and replaced dwelling services, and installers add them routinely with EV charger and solar work to protect the electronics.
Where it sits in the glossary
Surge protective device 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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