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Surge protection wrapper

Why you care (60 seconds)

Surge protection is now a common service requirement. Missing or misplacing SPDs can fail inspection and leave sensitive equipment exposed.

Where people lose time

  • Installing the SPD too far from the service equipment.
  • Using the wrong SPD type for the location.
  • Forgetting required labeling or documentation.

This is

The rule in plain language

Provide a listed surge protective device at required service locations using approved installation methods.

When it applies

New or modified services where the code requires SPD installation.

What you must do (checklist)

  • Confirm the service requires an SPD.
  • Select a listed SPD for the service equipment.
  • Install per manufacturer instructions and minimize lead length.
  • Label and document the installation.

Quick examples

  • A service panel with an integral SPD meets the requirement.
  • External SPDs must be located to keep leads short and protected.

This is not

Common misreads

  • Treating a plug-in SPD as a service SPD.
  • Installing an SPD without verifying listing requirements.

What it doesn't cover

  • Detailed surge coordination for critical facilities.
  • Lightning protection system requirements.

False friends

  • A surge device for point-of-use does not satisfy service SPD rules.

Exceptions & edge cases

  • Some occupancies have added SPD requirements.
  • Replacement services may require SPD retrofits.

Cross-references (NEC map)

  • Primary: 230.67
  • Secondary: 242

Exam traps

  • Mixing SPD types and installation locations.
  • Missing that an SPD is required at service equipment.

Field notes

  • Keep SPD datasheets in the closeout packet.
  • Verify lead length during installation to optimize performance.

AHJ / Local amendments notes (placeholder)

  • Add local amendments or interpretations here.

Revision notes

  • Draft wrapper created for surge protection fundamentals.