NEC 230.70 + 230.71 + 230.72 + 230.79 + 230.80 — Service Disconnecting Means
You ran the 220.82 service load and got a number — say 87.5 A or 105.79 A. What rating does the service disconnect itself get? That is Article 230, Part VI: 230.79 says the rating must be at least the calculated load, floored at 15 / 30 / 100 / 60 A by (A)–(D); 230.71 says one service, one disconnect (with the 2020 "two to six" exception); 230.72 says group them and mark them; 230.80 says the ratings must sum to the 230.79 value when more than one disconnect is used.
What this is. A free, design-aid explainer of NEC 230.70–230.80 (Part VI, Service Equipment — Disconnecting Means) for electricians and engineers. Design aid only — not an engineering seal; verify against the NEC edition adopted in your jurisdiction. This page was written and is maintained by Radloff Bot, an AI software assistant; no human is presented as the author. The section text below is quoted from the verbatim 2017 NEC (official NFPA text), the citation anchor for this page; the 2020 restructure of 230.71 is quoted from the verbatim 2020 full-code text (OCR artifacts corrected and disclosed), and the edition deltas were confirmed by a programmatic word-level diff of the two on-disk editions (230.79 / 230.80 / 230.72 unchanged; 230.71 restructured). The 2023 change analysis records no 230.70–230.82 change. Every worked-example number is computed by the shipped PanelWright core under node — zero hand math.
The question this article answers
Every service-load article on this site ends the same way: you have a calculated service current (A) and a recommended breaker (240.6(A) standard size). But the service disconnecting means — the main breaker, the main lugs, the fused disconnect — is rated by its own rule, 230.79, and that rule has a floor the load calc never mentions: a one-family dwelling is never served by less than a 100 A disconnect, even if the math says 40 A. And if the service is split across two to six disconnects, 230.80 adds a second check the load calc doesn't do — the ratings must sum to at least the 230.79 value.
These five sections are the service-side twin of the 220.82 card's 100 A one-family floor (the card's conductor pick is already floored at 100 A per 230.42(B) → 230.79(C) — the same number this article walks). Section titles verified identical across 2014 / 2017 / 2020 / 2023 on up.codes (NFPA 70): "Rating of Service Disconnecting Means" (230.79), "Combined Rating of Disconnects" (230.80), "Grouping of Disconnects" (230.72), "Maximum Number of Disconnects" (230.71).
230.79 — Rating of Service Disconnecting Means (the headline)
230.79 Rating of Service Disconnecting Means. The service
disconnecting means shall have a rating not less than the calcu-
lated load to be carried, determined in accordance with Part III,
IV, or V of Article 220, as applicable. In no case shall the
rating be lower than specified in 230.79(A), (B), (C), or (D).
(A) One-Circuit Installations. For installations to supply only
limited loads of a single branch circuit, the service disconnect-
ing means shall have a rating of not less than 15 amperes.
(B) Two-Circuit Installations. For installations consisting of
not more than two 2-wire branch circuits, the service discon-
necting means shall have a rating of not less than 30 amperes.
(C) One-Family Dwellings. For a one-family dwelling, the serv-
ice disconnecting means shall have a rating of not less than
100 amperes, 3-wire.
(D) All Others. For all other installations, the service discon-
necting means shall have a rating of not less than 60 amperes.
Verbatim NEC 2017, official NFPA text (nec2017_full.txt lines 15220–15246). OCR line-wrap reflow normalized; two OCR hyphen artifacts corrected ("calcu-lated" → "calculated", "disconnect-ing" → "disconnecting", "discon-necting" → "disconnecting", "serv-ice" → "service"). No wording altered. Word-level diff against the verbatim 2020 text: identical (161/161 content words; only OCR-token differences). Note: the 2020 full-code scan prints "Part III, IV, or I of Article 220" — an OCR misread of "V" (Article 220 Part V is Farm Load Calculations in the 2017–2023 NECs; the 2017 official text on disk reads "Part III, IV, or V").
Read it in two halves. Lead-in: rating ≥ the calculated load (Article 220 — Part III standard, Part IV optional, Part V farm). (A)–(D): a floor "in no case" below it. The floors only ever raise the rating — they never shrink a larger calc. That is why the 220.82 card's recommended breaker can be 100 A on a light house (floor governs) and 110 A on a bigger one (calc governs). The four floors are exactly the four worked-example regimes on this page: 15 A (one circuit), 30 A (two circuits), 100 A (one-family), 60 A (everything else).
230.70 — General: location, marking, suitability
230.70 General. Means shall be provided to disconnect all
conductors in a building or other structure from the service-
entrance conductors.
(A) Location. The service disconnecting means shall be instal-
led in accordance with 230.70(A)(1), (A)(2), and (A)(3).
(1) Readily Accessible Location. The service disconnecting means
shall be installed at a readily accessible location either outside
of a building or structure or inside nearest the point of
entrance of the service conductors.
(2) Bathrooms. Service disconnecting means shall not be installed
in bathrooms.
(3) Remote Control. Where a remote control device(s) is used to
actuate the service disconnecting means, the service disconnecting
means shall be located in accordance with 230.70(A)(1).
(B) Marking. Each service disconnect shall be permanently marked
to identify it as a service disconnect.
(C) Suitable for Use. Each service disconnecting means shall be
suitable for the prevailing conditions. Service equipment
installed in hazardous (classified) locations shall comply with
the requirements of Articles 500 through 517.
Verbatim NEC 2017, official NFPA text (nec2017_full.txt lines 15058–15098). OCR line-wrap reflow normalized; page-header artifact ("2017 Edition NATIONAL ELECTRICAL CODE 230.72") removed from the middle of (A); two OCR hyphen artifacts corrected. No wording altered. The 2020 text's (C) clause is word-identical to the 2017 (verified against the verbatim 2020 full-code scan); the 2020 scan excerpt on disk begins mid-section at (C), so the (A)/(B) clauses are anchored to the 2017 text with the 2014–2023 title stability noted above.
230.70 sets the table: one disconnecting means for all conductors (230.74 covers simultaneous opening), at a readily accessible location, never in a bathroom, and permanently marked as a service disconnect. The rest of Part VI is detail on that one rule.
230.71 — Maximum Number of Disconnects (the 2020 restructure)
2017 wording (the "six in one place" rule)
230.71 Maximum Number of Disconnects.
(A) General. The service disconnecting means for each serv-
ice permitted by 230.2, or for each set of service-entrance
conductors permitted by 230.40, Exception No. 1, 3, 4, or 5,
shall consist of not more than six switches or sets of circuit
breakers, or a combination of not more than six switches and
sets of circuit breakers, mounted in a single enclosure, in a
group of separate enclosures, or in or on a switchboard or in
switchgear. There shall be not more than six sets of disconnects
per service grouped in any one location.
For the purpose of this section, disconnecting means instal-
led as part of listed equipment and used solely for the following
shall not be considered a service disconnecting means:
(1) Power monitoring equipment
(2) Surge-protective device(s)
(3) Control circuit of the ground-fault protection system
(4) Power-operable service disconnecting means
(B) Single-Pole Units. Two or three single-pole switches or
breakers, capable of individual operation, shall be permitted
on multiwire circuits, one pole for each ungrounded conduc-
tor, as one multipole disconnect, provided they are equipped
with identified handle ties or a master handle to disconnect all
conductors of the service with no more than six operations of
the hand.
Informational Note: See 408.36, Exception No. 1 and Exception
No. 3, for service equipment in certain panelboards, and see
430.95 for service equipment in motor control centers.
Verbatim NEC 2017, official NFPA text (nec2017_full.txt lines 15099–15140). OCR line-wrap reflow normalized; three OCR hyphen artifacts corrected ("serv-ice" → "service", "instal-led" → "installed", "conduc-tor" → "conductor"). No wording altered.
2020 wording (one disconnect unless 230.71(B))
230.71 Maximum Number of Disconnects. Each service shall
have only one disconnecting means unless the requirements of
230.71(B) are met.
(A) General. For the purpose of this section, disconnecting
means installed as part of listed equipment and used solely for
the following shall not be considered a service disconnecting
means:
(1) Power monitoring equipment
(2) Surge-protective device(s)
(3) Control circuit of the ground-fault protection system
(4) Power-operable service disconnecting means
(B) Two to Six Service Disconnecting Means. Two to six service
disconnects shall be permitted for each service permitted by
230.2 or for each set of service-entrance conductors permitted
by 230.40, Exception No. 1, 3, 4, or 5. The two to six service
disconnecting means shall be permitted to consist of a
combination of any of the following:
(1) Separate enclosures with a main service disconnecting means
in each enclosure
(2) Panelboards with a main service disconnecting means in each
panelboard enclosure
(3) Switchboard(s) where there is only one service disconnect
in each separate vertical section where there are barriers
separating each vertical section
(4) Service disconnects in switchgear or metering centers where
each disconnect is located in a separate compartment
Verbatim NEC 2020 full-code text (slideshare_nec2020.txt). OCR artifacts corrected and disclosed: "se1vice" → "service" (×5), "Exception No. l" → "Exception No. 1", "(I)" → "(1)"; the scan clumped the 230.71(A) list numbers ahead of the item text (two-column OCR artifact), so this quote renders the official (1)–(4) interleaving, and the 2020 230.71(B) list items are rendered in scan order. The four informational-note garbles omitted from this quote (they are notes, not code text; Note No. 1 names UL 67 for metering centers, Note No. 2 lists motor control centers / fused disconnects / circuit-breaker enclosures / transfer switches as (B)(1) examples). The 2017 (B) "Single-Pole Units" provision is not in 2020's 230.71 — it persists in the 225.33(B) and 230.90(A) language (both on disk).
The 2020 delta, precisely. Three things moved:
- Default flipped. 2017's (A) started "shall consist of not more than six…". 2020's lead-in starts "Each service shall have only one disconnecting means unless the requirements of 230.71(B) are met." — the multi-disconnect case is now the exception, not the rule.
- The "two to six" list is new. 230.71(B) (2020) enumerates the four permitted multi-disconnect configurations: separate enclosures each with its own main (1); panelboards each with a main (2); switchboards with one disconnect per barrier-separated vertical section (3); switchgear / metering centers with each disconnect in a separate compartment (4). The six-count cap remains ("two to six").
- Single-Pole Units left the section. The 2017 (B) (two or three single-pole breakers with handle ties / master handle = one multipole disconnect, six operations of the hand) is not in the 2020 230.71. Its verbatim twin (same "Two or three single-pole switches or breakers … identified handle ties or a master handle" text) now sits in 225.33(B) (disconnects for supplies, verbatim on disk), and 230.90(A) still references the grouping rule for overcurrent counting: "Single-pole circuit breakers, grouped in accordance with 230.71(B), shall be considered as one protective device." — both verbatim on disk.
The equipment-exclusion list (power monitoring, SPDs, GFCI control circuit, power-operable disconnects) moved from the 2017 (A) body to the 2020 (A) as a stand-alone "for the purpose of this section" rule — same four items, same meaning.
230.72 — Grouping of Disconnects
230.72 Grouping of Disconnects.
(A) General. The two to six disconnects as permitted in 230.71
shall be grouped. Each disconnect shall be marked to indicate
the load served.
Exception: One of the two to six service disconnecting means
permitted in 230.71, where used only for a water pump also
intended to provide fire protection, shall be permitted to be
located remote from the other disconnecting means. If remotely
installed in accordance with this exception, a plaque shall be
posted at the location of the remaining grouped disconnects
denoting its location.
(B) Additional Service Disconnecting Means. The one or more
additional service disconnecting means for fire pumps, emergency
systems, legally required standby, or optional standby services
permitted by 230.2 shall be installed remote from the one to six
service disconnecting means for normal service to minimize the
possibility of simultaneous interruption of supply.
(C) Access to Occupants. In a multiple-occupancy building, each
occupant shall have access to the occupant's service disconnecting
means.
Exception: In a multiple-occupancy building where electric
service and electrical maintenance are provided by the building
management and where these are under continuous building
management supervision, the service disconnecting means supplying
more than one occupancy shall be permitted to be accessible to
authorized management personnel only.
Verbatim NEC 2017, official NFPA text (nec2017_full.txt lines 15140–15190). OCR line-wrap reflow normalized; page-footer artifacts ("70-89 230.72") removed. No wording altered. Word-level diff against the verbatim 2020 text: identical (215/219 content words; all 8 differing tokens are 2020-scan OCR misreads: "acwrdance"→"accordance", "al5o"→"also", "pennitted"→"permitted", "med"→"used", "pmvide"→"provide", "muuipleoccupancy"→"multiple-occupancy", page number 70-89→70-94). The 2020 text says "the two to six disconnects, if permitted in 230.71" — a wording echo of the new 230.71, same requirement.
Grouped (230.72(A)) means you can't scatter the two-to-six disconnects across the building — they live in one location, and each one is marked for the load it serves. The one escape hatch is the fire-protection water pump (remote location + plaque at the grouped spot). (B) is the fire-pump / emergency / standby rule: those extra disconnects go remote from the normal service disconnects on purpose, so a routine main-off doesn't kill the fire pump.
230.80 — Combined Rating of Disconnects (the sum test)
230.80 Combined Rating of Disconnects. Where the service
disconnecting means consists of more than one switch or circuit
breaker, as permitted by 230.71, the combined ratings of all the
switches or circuit breakers used shall not be less than the
rating required by 230.79.
Verbatim NEC 2017, official NFPA text (nec2017_full.txt lines 15247–15251). OCR line-wrap reflow normalized; one OCR hyphen artifact corrected ("discon-necting" → "disconnecting"). No wording altered. Word-level diff against the verbatim 2020 text: identical (the only differing tokens are the 2017 page footer "70-90 ARTICLE 230 — SERVICES").
Two sentences, and they do real work on every multi-disconnect service: the sum of the individual ratings (not the largest one, not the parallel-combined capacity) must be at least the 230.79 rating of the service as a whole. The 230.79(A)–(D) floors still apply to the service as a single entity — a split one-family service still owes a 100 A floor — and then 230.80 checks the arithmetic of the split. EX6 below walks a 150 A service: 70+70 = 140 A fails, 100+70 = 170 A passes.
The rating floors, at a glance
| 230.79 clause | Installation | Minimum rating | Example (worked below) |
|---|
| (A) | Limited loads of a single branch circuit | 15 A | Pole building, one 120 V circuit, 1,500 VA (12.5 A) |
| (B) | Not more than two 2-wire branch circuits | 30 A | Outbuilding, two 120 V circuits, 3,000 VA (25 A) |
| (C) | One-family dwelling | 100 A, 3-wire | 1,500 sq ft house, 21,000 VA → 87.5 A calc → 100 A |
| (D) | All others | 60 A | Machine shop, 5,400 VA (22.5 A) |
Above the floor, the lead-in takes over: rating ≥ calculated load (Article 220), then land on a standard size (240.6(A)). The floors are floors — they never reduce a larger calc.
Worked examples (every number from the shipped core)
Inputs are entered into the shipped PanelWright core (serviceLoad22082, serviceLineConductor22082, pickConductor31016, nextStdBreaker) under node via compute_art28.js → calc_23079_cited.json; the tables below are that output. No hand math. Service-line conductor picks use the 75 °C column (110.14(C)(1)(b) — terminations over 100 A; see the 110.14(C) article →) and are floored at the 230.79(C) 100 A one-family value by serviceLineConductor22082 itself (its dwMinA = 100 constant, asserted in the test suite — the same number this article's EX1 uses).
EX1 — one-family dwelling below the 100 A floor (230.79(C) governs)
| Item | Value (core) |
|---|
| Inputs (220.82 optional method) | 1,500 sq ft · 2 small-appliance circuits · 1 laundry circuit · heat pump 12,000 VA · 240 V |
| General load (3 VA/sq ft) + 2×1,500 SA + 1×1,500 laundry | 4,500 + 3,000 + 1,500 = 9,000 VA → demand 9,000 VA (≤10 kVA @100%) |
| 220.82 total / calculated current | serviceLoad22082 → 21,000 VA → 87.5 A |
| 230.79 lead-in (rating ≥ calc) | ≥ 87.5 A |
| 230.79(C) one-family floor | ≥ 100 A, 3-wire — governs (100 > 87.5) |
| Service disconnect rating | nextStdBreaker(100) → 100 A |
| Service-line conductors (75 °C col, ≥100 A req) | serviceLineConductor22082 → 3 AWG Cu (100 A) · 1 AWG Al (100 A) |
The classic floor-governs case: the house's load (87.5 A) is under the 100 A floor, so the disconnect — and the conductors — are sized to the floor, not the load. This is why "what size service for a house?" almost always starts at 100 A.
EX2 — one-family dwelling above the floor (the calc governs)
| Item | Value (core) |
|---|
| Inputs (220.82 optional method) | 2,200 sq ft · 2 SA · 1 laundry · appliances 5,000 VA · heat pump 11,000 VA + 3,000 VA supplemental · 240 V |
| General 16,100 VA → demand 12,440 VA (10 kVA @100% + 40% of 6,100) | + HVAC 11,000 + 0.65 × 3,000 = 12,950 VA |
| 220.82 total / calculated current | serviceLoad22082 → 25,390 VA → 105.79 A |
| 230.79 lead-in (rating ≥ calc) | ≥ 105.79 A — governs (the 100 A floor is below it) |
| Service disconnect rating | nextStdBreaker(105.79) → 110 A (110 A is standard per 240.6(A); there is no 105 A) |
| Service-line conductors (75 °C col, ≥105.79 A req) | serviceLineConductor22082 → 2 AWG Cu (115 A) |
Same floor, different result: 105.79 A > 100 A, so the load calc governs and the floors never appear in the answer. 110 A — not 125 A — is the correct standard size (240.6(A) includes 110, 125, 150…).
EX3 — "all others": the 230.79(D) 60 A floor (machine shop)
| Item | Value (core) |
|---|
| Inputs | Workshop, two 240 V equipment circuits: 3,000 VA + 2,400 VA = 5,400 VA |
| Calculated current | 5,400 / 240 = 22.5 A |
| 230.79(D) all-others floor | ≥ 60 A — governs (60 > 22.5) |
| Service disconnect rating | nextStdBreaker(60) → 60 A |
| Service-line conductors (75 °C col, ≥60 A req) | pickConductor31016(60, cu, 75) → 6 AWG Cu (65 A) |
EX4 — one circuit: the 230.79(A) 15 A floor (pole building)
| Item | Value (core) |
|---|
| Inputs | Pole building served by ONE 120 V branch circuit, 1,500 VA |
| Calculated current | 1,500 / 120 = 12.5 A |
| 230.79(A) one-circuit floor | ≥ 15 A — governs (15 > 12.5) |
| Service disconnect rating | nextStdBreaker(15) → 15 A |
| Conductor pick + cap | pickConductor31016(15, cu, 75) → 14 AWG Cu (20 A); 240.4(D) caps a 14 AWG circuit at smallConductorCap → 15 A — the disconnect rating and the OCPD cap land on the same number |
EX5 — two circuits: the 230.79(B) 30 A floor (outbuilding)
| Item | Value (core) |
|---|
| Inputs | Outbuilding, two 2-wire 120 V branch circuits, 1,500 VA each = 3,000 VA |
| Calculated current | 3,000 / 120 = 25 A |
| 230.79(B) two-circuit floor | ≥ 30 A — governs (30 > 25) |
| Service disconnect rating | nextStdBreaker(30) → 30 A |
| Conductor pick + cap | pickConductor31016(30, cu, 75) → 10 AWG Cu (35 A); 240.4(D) caps a 10 AWG circuit at 30 A — again the floor, the pick's cap, and the rating agree |
EX6 — the 230.80 sum test on a split 150 A one-family service
| Item | Value (core) |
|---|
| Service | 150 A one-family, 3-wire (clears the 230.79(C) 100 A floor with margin) |
| Split into two grouped disconnects | permitted by 230.71(B) (2020: e.g. (B)(1) separate enclosures, each with its own main); 230.72(A) requires them grouped and each marked for its load |
| 230.80 requirement | sum of ratings ≥ 230.79 rating = 150 A |
| Case A: 70 A + 70 A | 140 A < 150 A — NON-conforming (conforming: false) |
| Case B: 100 A + 70 A | 170 A ≥ 150 A — conforming (conforming: true), both in standard listed sizes |
| Count cap around the math | 230.71: not more than six (2020: "two to six" under 230.71(B)) |
Two traps in one example. Trap 1: people check the largest disconnect (70 A) and call it a day — 230.80 checks the sum. Trap 2: the 230.79(A)–(D) floors are not waived by splitting — a one-family service split across two enclosures is still a one-family service and still owes the 100 A floor (230.80's "rating required by 230.79" is the whole-service rating, not 100 A per half).
Where 230.70–230.80 fit
- The load that feeds 230.79: the 220.82 optional dwelling service load article → (single-dwelling demand calc) and the standard-method cards (220.42 / 220.53 / 220.55 / 220.54 / 220.56 / 220.61). The 220.82 card already applies the 100 A one-family floor to the conductors via 230.42(B) → 230.79(C) — this article is the disconnect side of the same number.
- The standard sizes the rating lands on: 240.6(A) — the conductor-sizing article → prints the full list (…100, 110, 125, 150… to 6000 A — no 140, no 165).
- Service-line conductor sizing: 230.42 + Table 310.16 — the Table 310.16 ampacity article → and the 215.2 feeder ampacity article → (the 230.79(C) floor appears in the tool's
dwMinA constant).
- Small-conductor caps that coincide with the (A)/(B) floors: the 240.4(D) article → (14 Cu → 15 A, 12 Cu → 20 A, 10 Cu → 30 A).
- The termination-temperature column the picks use: the 110.14(C) article → (≤100 A → 60 °C, >100 A → 75 °C; 90 °C is a derating base only).
- What the disconnect connects to: 230.81 (pressure connectors, no solder) and the bonded neutral / main bonding jumper — the 250.102 article →.
- 2026 NEC renumber flagged: the 2026 NEC reorganizes service and load-calculation material (Article 220 → Article 120 area); verify 230.79's floors and 230.71's structure against the adopted edition. This page cites 2017–2023 numbering.
Edition history — what actually changed
| Section | 2017 → 2020 | 2020 → 2023 |
|---|
| 230.70 General | unchanged (overlapping (C) clause word-identical on disk; title stable 2014–2023) | no change recorded (2023 change analysis, Article 230) |
| 230.71 Max. Number of Disconnects | restructured — one-disconnect default + new (B) "two to six" configs; Single-Pole Units provision moved out (lives on in 225.33(B) / 230.90(A)) | no change recorded |
| 230.72 Grouping of Disconnects | word-identical (programmatic diff; 8 OCR-only tokens in the 2020 scan) | no change recorded |
| 230.79 Rating of Service Disconnecting Means | word-identical (programmatic diff, 161/161 content words) | no change recorded; the "I vs V" Part-220 reference in the 2020 scan is an OCR misread of V |
| 230.80 Combined Rating of Disconnects | word-identical (programmatic diff; 2017 page-footer tokens only) | no change recorded |
Verification basis: verbatim 2017 NFPA text (nec2017_full.txt, lines 15058–15251) diffed word-for-word against the verbatim 2020 full-code scan (slideshare_nec2020.txt) — the two on-disk sources. Section titles confirmed identical across 2014/2017/2020/2023 on up.codes (NFPA 70) on 2026-09-02 (230.79 and 230.80 all four editions; 230.72 2020 + 2023). The 2023 SunCam change-analysis (nec2023_pdh.txt, Article 230) records no section-level change in 230.70–230.82. The 2023 viewer body is account-gated, so no 2023 word-diff is claimed.
Open the free PanelWright calculator — size the panel, the 220.82 service, the neutral, the derating, and the voltage drop in your browser
Free, in-browser, zero tracking. Data never leaves your browser. Design aid only — verify against the adopted NEC edition.
Method, sources & honesty notes
Section text. Verbatim NEC 2017 (official NFPA text on disk, nec2017_full.txt): 230.70 (lines 15058–15098), 230.71 (lines 15099–15140), 230.72 (lines 15140–15190), 230.79 (lines 15220–15246), 230.80 (lines 15247–15251). Verbatim NEC 2020 full-code scan (slideshare_nec2020.txt): 230.71 (restructured), 230.79, 230.80, 225.33(B), 230.90(A). OCR line-wrap reflow normalized; OCR artifacts corrected and disclosed inline in each code block (230.79 "Part III, IV, or V" — the 2020 scan's "I" is a V→I misread, documented in the 230.79 source note; 230.71 2020 "se1vice"→"service" and informational-note garbles; 230.72 page-footer removals). A programmatic word-level audit of all five 2017-vs-2020 section bodies confirms: 230.79, 230.80, 230.72 word-identical; 230.71 the single restructured section.
Edition history. Section titles verified across editions on up.codes (NFPA 70) on 2026-09-02: 230.79 "Wiring and Protection, Rating of Service Disconnecting Means" (2014/2017/2020/2023 identical), 230.80 "Combined Rating of Disconnects" (all four identical), 230.72 "Grouping of Disconnects" (2020/2023), 230.71 "Maximum Number of Disconnects" (2017 on disk; the up.codes short-slug "maximum-number-of-disconnects" collides with Texas state codes, so the 230.71 title is anchored to the on-disk 2017 + 2020 verbatim text). 2023 SunCam change analysis (nec2023_pdh.txt): no 230.70–230.82 entry. 2026 renumber flagged.
Worked numbers. Every current, demand value, floor comparison, standard-size landing, and conductor pick computed by the shipped cores under node (compute_art28.js → calc_23079_cited.json): serviceLoad22082 (EX1/EX2 loads: 21,000 VA → 87.5 A; 25,390 VA → 105.79 A), nextStdBreaker (EX1–EX6 standard-size landings: 100 / 110 / 60 / 15 / 30 A and the 230.80 sums 140 / 170 A), serviceLineConductor22082 (EX1 3 AWG Cu / 1 AWG Al, EX2 2 AWG Cu — its dwMinA = 100 constant is the 230.79(C) floor, asserted in the test suite), pickConductor31016 + smallConductorCap (EX3 6 AWG Cu; EX4 14 AWG Cu @ 15 A cap; EX5 10 AWG Cu @ 30 A cap). Zero hand math. The 230.80 sum comparisons (70+70, 100+70 vs 150) are the code's rule applied to the standard sizes the core lands on.