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Surge Protection Device (SPD) Rating Calculator

Recommends an SPD Type by installation location, computes a minimum recommended MCOV from system voltage and grounding configuration, and checks a candidate SPD's SCCR against the available fault current.

AAJappsEngineering Calculation Report

Surge Protection Device (SPD) Rating Calculator

NEC 230.67, 242, 285.6/285.7 — SPD type, MCOV and SCCR selection

Generated

For preliminary engineering use only — always verify results against project-specific standards and a qualified engineer's review before use in a real design.

System

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Candidate SPD

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SPD rating result

Recommended SPD TypeType 1 (line side) or Type 2 (load side of main disconnect)
Reference voltage277.1 V
Minimum recommended MCOV318.7 V
Candidate MCOV adequateYes
Candidate SCCR adequateYes
ADEQUATE ✓