NEC 422.30–422.62 — Appliance Disconnecting Means, Construction & Marking

The Article 422 series so far: the branch-circuit core (422.10–422.13, article 56) and the Part II installation rules (422.15–422.22, article 58). This article is the companion that closes Article 422 on the on-disk record: Part III Disconnecting Means (422.30–422.35) — which device may be the appliance's disconnect, the 300 VA / 1/8 hp boundary of 422.31(A), the receptacle-as-disconnect route of 422.33, and the unit-switch rules of 422.34; Part IV Construction (422.40–422.50) — polarity, immersion protection, heated-appliance signals, water-heater limit means, and infrared-lamp lampholders (with 422.46 and 422.50 deleted outright in 2023); and Part V Marking (422.60–422.62) — what the nameplate must say, including the 430.110(C)(1) combined-horsepower hook. Eight verified 2017→2023 deltas (including the 422.31(C) "more than 4 hp" gate removal and the Mike Holt-documented 422.33(B) drawer clarification), 75 machine-verified checks, plus five worked examples from the shipped cores.

Part III — Disconnecting Means (422.30–422.35), verbatim 2017

The five sections of Part III — the answer to "what switch actually kills this appliance":

The 2017→2023 edition story — Part III (8 deltas, machine-verified)

Part IV — Construction (422.40–422.50), verbatim 2017

The nine Part IV sections on disk, in order. 422.43 (flexible cords / heater cords) sits between 422.42 and 422.44 but is covered by the 422.16 article (58) — it was deleted in 2023 and its (A) heater-cord rule relocated to 422.16(A)(3), so it is out of scope here. The two sections 2023 deletes outright — 422.46 and 422.50 — are quoted and flagged.

Part V — Marking (422.60–422.62), verbatim 2017

Every 2017→2023 delta in this article, in one table

Unchanged (word-identical 2017→2023, machine-verified): 422.30, 422.33(A), 422.33(C), 422.34 (lead + (A)–(D)), 422.35, 422.42, 422.44, 422.45, 422.48(A), 422.48(B), 422.60(A) core + IN, 422.60(B), 422.61, 422.62(B)(1), 422.62(B)(2) — sixteen identity checks, all passing. No percentage, ampere, watt, or horsepower number in Parts III–V moved between editions. The 422.62(A) "motor operated" → "motor-operated" hyphen and the 430.110(C)(1) spacing are the only Part V surface changes.

Worked examples (core-computed)

Every rating below is computed by the shipped PanelWright cores under node (compute_art59.js → art59_numbers.json) — nextStdBreaker (240.6 standard sizes), pickConductor31016 (Table 310.16), reqBreakerA (210.20(A) 125% continuous). Zero hand math.

EX1 — the 422.33(C) receptacle floor: a 50 A range on a 40 A receptacle

A 12,000 W / 240 V household electric range is cord-and-plug connected, so the accessible plug + receptacle IS the disconnecting means (422.33(A)). 422.33(C) then sets the floor: the receptacle rating must not be less than the rating of any appliance connected to it.

The 422.33(C) Exception permits demand factors authorized elsewhere in this Code to be applied to the receptacle/connector rating — that is the multi-appliance case (e.g. a receptacle serving several small appliances), not a way to under-rate a single connected appliance: "not less than the rating of any appliance connected thereto" is the floor, and a 40 A receptacle on a 50 A appliance is below it.

EX2 — the 422.33(B) range drawer rule (the 2023 clarification made concrete)

A 10,800 W / 240 V range has its attachment plug and receptacle at the rear base, accessible from the front by removal of a drawer. In 2017 that connection "shall meet the intent of 422.33(A)"; in 2023 it "shall be permitted" — the Mike Holt-documented clarification that drawer removal establishes the accessibility 422.33(A) demands. The numbers are the route's numbers:

Note the 45 A OCPD: 240.6's standard list contains 45 A (unlike, say, 75 A, which steps to 80 A in the multi-motor article (57)). The 45 A device sits in the 422.33(C) floor and the Table 310.16 8 AWG pick at the same time — the receptacle, the OCPD, and the conductor all agree at 45/50 A.

EX3 — the 422.31(A)/(B) boundary: 300 VA at 115 V

422.31 routes permanently connected appliances by the 300 VA / 1/8 hp boundary. At 115 V (a typical small-appliance circuit voltage) the boundary lands at 300 ÷ 115 = 2.61 A:

The two rows land on the same 15 A OCPD (both round up to the 240.6 floor) — the boundary changes the routing language (overcurrent device vs switch/breaker, and which of 422.31(A)/(B) you cite on the panel schedule), not the device. That is the point of the 300 VA threshold: small permanently connected appliances are allowed to live on their breaker alone, so long as it is in sight or lockable.

EX4 — 422.31(C) + 430.110(C)(1): the disconnect rating on a motor-operated appliance, and the 4-hp gate delta

A permanently connected motor-operated appliance: ½ hp motor (208 V, Table 430.248 full-load current = 4.0 A, transcribed from the on-disk 2017 scan) + 250 W / 230 V control load (1.09 A). 422.31(C) says the disconnecting means must comply with 430.109 and 430.110 — and 430.110(C)(1) (the on-disk 2023 row) rates it from the sum of all currents at the full-load condition:

And the edition delta, made concrete: under 2017 422.31(C), this 0.5 hp appliance fails the "of more than 4 hp" gate — its disconnecting means had to be in sight or lockable-open (110.25), full stop. Under 2023, the gate is gone: if the appliance has a unit switch complying with 422.34(A), (B), or (C), the other disconnecting means (the branch-circuit device) is permitted out of sight. Same 5.09 A / 15 A rating in both editions — the delta is purely the sight/lock condition a designer gets to rely on. (The full 430.101–430.113 disconnecting-means rules live in the motor disconnecting-means article (42).)

EX5 — 422.47 water-heater limit means (with the Ex 1 60 kW test) + the 422.48 300 W lamp boundary

First, the heater: a 4,500 W / 240 V storage water heater (continuous per 422.13 — article 56) must have a temperature-limiting means in addition to its control thermostat that (1) senses maximum water temperature and (2) is trip-free manually reset or a replacement-element type, plus the T&P-valve marking. Exception 1 exempts storage heaters identified for 82 °C (180 °F) supply at 60 kW or above — this 4.5 kW unit is far from the exemption (4.5 < 60):

Second, the infrared lamps of 422.48 — the 300 W boundary that splits the permitted lampholders:

The boundary is inclusive: "rated at 300 watts or less" admits the 300 W lamp to the simple medium-base unswitched porcelain holder; one watt over and the identified-holders requirement of (B) applies. (The deleted 422.46/422.50 sit beside these in Part IV — the flatiron's "identified temperature-limiting means" and the pipe-heating-assembly listing requirement both had a 2017 home and a 2023 absence.)

Where 422.30–422.62 fit

• The branch-circuit foundation this article extends: the NEC 422.10 + 422.11 + 422.12 + 422.13 appliance branch circuit (article 56) — 422.10/422.11 size the circuit and OCPD; 422.13 makes the water heater a 125% continuous load (EX5's 23.44 A / 25 A / 12 AWG package is that article's EX1 re-run); this article is what happens AFTER the circuit is sized — the disconnect, the construction, the marking.
• The Part II installation neighbor: the NEC 422.16 + 422.18 + 422.22 flexible-cords / ceiling-fan-support article (58) — 422.16's cord-and-plug conditions feed directly into 422.33 (the cord's plug IS a candidate disconnecting means); its documented 422.15/422.43 deletions frame this article's 422.46/422.50 deletions.
• The motor-side rules 422.31(C) hangs on: the NEC 430.101–430.113 disconnecting means (article 42) — 422.31(C)'s "comply with 430.109 and 430.110" is a direct hand-off, and EX4's 430.110(C)(1) sum (4.0 + 1.09 = 5.09 A → 15 A) is that article's combined-loads rule applied to an appliance.
• The single-motor circuit this appliance would sit on: the NEC 430.22 + 430.52 single-motor branch circuit (article 38) — the 125% FLC conductor rule and Table 430.52 OCPD values that a motor-operated appliance's branch circuit follows.
• The OCPD catalog and the conductor table behind every rating above: the NEC 240.6 standard ampere ratings (the 15 A floor in EX3/EX4, the 45 A standard size in EX2, the 25 A step in EX5) and the Table 310.16 allowable ampacities (the 8 AWG / 12 AWG picks).

Scope boundary, stated: this article is exactly 422.30–422.35 (Part III), 422.40–422.50 (Part IV, with 422.43 excluded — it belongs to article 58), and 422.60–422.62 (Part V). 422.1–422.13 (General + branch circuits — article 56), 422.15–422.22 (Part II installation — article 58), and Article 424 (fixed electric space-heating, where 2023 moved the branch-circuit rules to 424.4) are adjacent scope outside this article. 2020 position is not asserted: no on-disk 2020 source carries the 422.30–422.62 section bodies (the on-disk 2020 scan ends before Article 422; verified), so the edition story is 2017↔2023 only. 2026 edition (flagged honestly): no on-disk source confirms the 422.30–422.62 section numbers moved for the 2026 cycle, so this page cites them as stable across 2017–2023 and presents the 2017↔2023 deltas above. Verify section numbers against the NEC edition adopted in your jurisdiction.

Method, sources & honesty notes