Quick Hits

PART VI — SERVICE EQUIPMENT — DISCONNECTING MEANS

EPISODE 10 — The Service Disconnect: Location, Type & Isolating Switches (268.70)

Slide 1 — Hook "New Part — and this first section alone (268.70) is packed. The service disconnect: where it goes, what it has to do, and isolating switches."

Slide 2 — 268.70(A) Location

• Must be readily accessible — either OUTSIDE the building, or INSIDE nearest the point where service conductors enter.

• If it's genuinely not readily accessible, it must be operable by mechanical linkage from a readily accessible point (or, for multibuilding industrial sites under single management, electrically operated by a readily accessible remote control).

• Exceptions: single-management sites with documented safe switching procedures and qualified-personnel monitoring can locate it elsewhere or behind a tool-required enclosure; certain electrolytic cell installations (685.1), lighting-standard poles/towers, and sign-support poles also get location flexibility.

Slide 3 — 268.70(C)–(E) Marking, Type & Isolating Switches

• Marking: every service disconnect must be permanently marked as a service disconnect.

• Type: must simultaneously disconnect all ungrounded service conductors it controls, and have a fault-closing rating not less than the available fault current at its terminals. (Exception: fused cutouts can skip simultaneous disconnection IF there's a way to disconnect the load first, with a required warning sign.)

• Isolating switches: if the disconnect itself doesn't have VISIBLE break contacts, a visible-break isolating switch is required on the supply side of the whole assembly — accessible to qualified persons only, and equipped with a way to ground the load-side conductors when disconnected from supply.

Slide 4 — Quiz + CTA Q: "If a service disconnecting means does not provide visible break contacts, what must be installed on its supply side?" A) A GFCI breaker B) An isolating switch with visible break contacts C) A second identical disconnect D) Nothing — visible break isn't required over 1000V

✅ Answer: B — 268.70(E)(1): a visible-break isolating switch is required in that case.

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