Quick Hits

EPISODE 11 — Inspections and Tests for over 1kva systems — Article 267 FINALE (267.42)

Slide 1 — Hook "Final episode of Article 267! A section unique to medium/high-voltage work: mandatory pre-energization testing."

Slide 2 — 267.42(A) What has to be tested before energizing

• The complete electrical system design — including protective/switching/control circuit settings — has to be prepared in advance, made available to the AHJ on request, and performance tested on-site when first installed.

• Specific required tests: instrument transformers (verify polarity/burden), protective relays (verify correct operation via current/voltage injection at the instrument transformer terminals), switching circuits (verify they actually operate the equipment), control/signal circuits (verify correct function/output), metering circuits (verify correct operation), full acceptance tests on all assemblies/equipment/conductors/systems, and phase-difference-based relays/metering (verified under actual load AFTER operation begins).

Slide 3 — 267.42(B) The paperwork

• A test report covering all of these results has to be delivered to the AHJ BEFORE the system is energized — not after. The AHJ needs documented proof everything checks out before power flows.

Slide 4 — Quiz + CTA Q: "When must the test report covering 267.42(A)'s required tests be delivered to the AHJ?" A) Within 30 days after energization B) Before energization C) Only if requested D) Test reports aren't required

✅ Answer: B — 267.42(B): the report must be delivered to the AHJ prior to energizing the system.

CTA: 🎉 That's a wrap on ALL of Article 267 — Outside Branch Circuits & Feeders Over 1000V! Follow for more daily quick-hit study notes as we continue through the medium-voltage articles.

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