Anatomy of a Solar Permit Set — Every Sheet, Explained

Sheet 1 of 11 · The contract with the reviewer

Cover

Before a reviewer checks a single wire, they check whether this set is even reviewable — for the right house, under the right code edition.

Sheet 1 · Cover — schematic

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Title block

What it is: Customer, site address, APN, AHJ, utility — repeated on every single sheet.
Why it matters: A permit set is a legal document about one specific building. If sheet 4 could belong to another house, the whole packet is unverifiable.
The code: Universal AHJ requirement
Without it: Reviewers reject sets whose sheets can't be tied to one address.

Sheet 2 of 11 · Where it lives, and how a firefighter gets to it

Site / Plot Plan

Two drawings in one: the property from above, and the roof up close. One proves the system fits the lot legally; the other proves someone can walk on that roof during a fire.

Sheet 2 · Site / Plot Plan — schematic

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Array laid out to scale

What it is: Every module drawn at true size on the real roof plane, with row and column spacing.
Why it matters: A count in a table can be fiction. A scaled layout proves the panels physically fit — including gaps, and after setbacks are removed.
The code: Drawn from measured roof dimensions
Without it: Arrays that don't fit get discovered on install day, not on paper.

Sheet 3 of 11 · Will the roof hold, and will the wind take it

Structural & Uplift

Solar adds weight for 25 years and gives wind something to grab. This sheet is where a roof is proven capable — or honestly flagged as needing an engineer.

Sheet 3 · Structural & Uplift — schematic

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Attachment cross-section

What it is: The stack: module, rail, flashed mount, lag bolt, shingle, decking, rafter.
Why it matters: This drawing answers the inspector's real question — what exactly is holding the array to the house, and does the bolt land in structure rather than plywood.
The code: Fastener embedment into framing, not sheathing
Without it: Attachments into decking alone: the classic failure that peels an array off in a storm.

Sheet 4 of 11 · The sheet reviewers read hardest

Three-Line Diagram

Every conductor, every device, every rating — from the first cell in the array to the utility's meter. If one sheet gets scrutinized line by line, it's this one.

Sheet 4 · Three-Line Diagram — schematic

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PV source circuits

What it is: Array, string count, module Voc/Isc, and the maximum-voltage calculation.
Why it matters: Cold weather raises open-circuit voltage. Size a string at 25 °C and a January morning can push it past the inverter's ceiling — a silent, expensive failure.
The code: NEC 690.7 — corrected Voc at record-low temperature
Without it: Damaged inverters and a violation the reviewer will catch first.

Sheet 5 of 11 · So the next person can read it

Color-Coded Wiring

The same system as Sheet 4, drawn the way an electrician's eye works: by color, by conductor kind, by what's carrying power versus data.

Sheet 5 · Color-Coded Wiring — schematic

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Conductor colors

What it is: L1 black, L2 red, neutral white, EGC green — drawn, not just described.
Why it matters: Color convention is how an electrician reads a panel at a glance, years later, without the drawings. It's institutional memory encoded in insulation.
The code: NEC 200.6 (grounded), 250.119 (EGC)
Without it: A future service call that starts with guessing which wire is which.

Sheet 6 of 11 · The bill of materials that has to be true

Equipment & Circuit Schedules

Tables where every device gets a quantity, a model, a rating and a UL listing — and every circuit gets its conductor, its breaker and its conduit fill.

Sheet 6 · Equipment & Circuit Schedules — schematic

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Equipment schedule

What it is: Quantity, description, model, rating, and the UL/ETL listing for every device.
Why it matters: California and many utilities require listed equipment. The listing is the evidence that a lab tested this device to fail safely.
The code: NEC 110.3(B); CEC-listed equipment
Without it: Unlisted gear — a rejection, and no third-party proof of safety.

Sheet 7 of 11 · Written for someone you'll never meet

Label & Placard Schedule

Every placard, its exact wording and where it goes. These labels are read by a firefighter at 3 a.m. and an electrician a decade from now.

Sheet 7 · Label & Placard Schedule — schematic

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Rapid shutdown label

What it is: The placard at the service marking that the PV system has rapid shutdown, with the initiator location.
Why it matters: A responder decides in seconds whether to cut into a roof. This label is the entire basis of that decision.
The code: NEC 690.56(C)
Without it: Firefighters must assume the array is live — and may refuse to work the roof.

Sheet 8 of 11 · The design grading itself

NEC Compliance Review

An itemized pass/fail against the code sections that actually get cited — each with the number, the math, and the verdict.

Sheet 8 · NEC Compliance Review — schematic

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690.7 — maximum system voltage

What it is: String voltage corrected for the coldest expected temperature, against the inverter's ceiling.
Why it matters: The check that keeps a January sunrise from exceeding equipment ratings.
The code: NEC 690.7
Without it: Inverter damage and a violation.

Sheet 9 of 11 · Can the house actually take this

Service Load Calculation

The dwelling's demand, itemized the way an inspector re-derives it — because they will.

Sheet 9 · Service Load Calculation — schematic

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The method

What it is: 220.82 for a new service, 220.83 for adding load to an existing one, 220.87 from metered demand.
Why it matters: Most solar goes on existing homes — where 220.83 or a year of real meter data tells the truth better than a generic formula.
The code: NEC 220.82 / 220.83 / 220.87
Without it: The wrong method produces a defensible-looking number that's simply inapplicable.

Sheet 10 of 11 · The other approval you need

Utility Interconnection

The AHJ approves the building work. The utility approves connecting to their grid. Two separate reviews — this sheet feeds the second.

Sheet 10 · Utility Interconnection — schematic

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Application data

What it is: Inverter model and AC output, grid-support listing, system size, POI, service rating.
Why it matters: Utilities run their own review against their own rules. Handing them these fields in one place is what keeps an interconnection from stalling for weeks.
The code: UL 1741-SB grid support
Without it: Back-and-forth with the utility while the install waits.

Sheet 11 of 11 · The manufacturer's word, attached

Reference Documents

Datasheets and installation manuals for the exact equipment specified. In a real approved set, these are often most of the page count.

Sheet 11 · Reference Documents — schematic

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Module datasheet

What it is: Manufacturer specs: Pmax, Voc, Isc, temperature coefficients, mechanical load rating.
Why it matters: Every string calculation on Sheet 4 traces back to these figures. Attaching the sheet lets a reviewer verify the inputs, not just the outputs.
The code: Required by most AHJs; CEC-listed in CA
Without it: Unverifiable assumptions underneath every electrical result.

Anatomy of a
solar permit set.
Every line, explained.

Cover

Site / Plot Plan

Structural & Uplift

Three-Line Diagram

Color-Coded Wiring

Equipment & Circuit Schedules

Label & Placard Schedule

NEC Compliance Review

Service Load Calculation

Utility Interconnection

Reference Documents

The whole set, at a glance

Now watch it build itself.

Anatomy of asolar permit set.Every line, explained.

The whole set, at a glance

Now watch it build itself.

Anatomy of a
solar permit set.
Every line, explained.