Template · Solar and storage

Grid-tied PV, string inverter single line diagram

Load-side connection through a 40A backfed breaker. Use this for a typical residential rooftop system with one string inverter, connected through a backfed breaker in the main panel. It suits a panel whose bus has room for the solar breaker under the busbar check.

A free template with typical ratings, conductor callouts and general notes. Open it, change what differs on your job, fill in the title block and export a PDF.

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Grid-tied PV, string inverter single line diagram: load-side connection through a 40A backfed breaker. — Grid-tied PV, string inverter. 11 devices on an 11 × 17 in sheet with a title block and notes column.

What the reviewer checks on this drawing

The reviewer checks the busbar arithmetic, the PV breaker at the opposite end of the bus from the main, the inverter output at 125%, the AC disconnect and rapid shutdown.

What the drawing shows

Every device on the sheet, in the order power reaches it.

Symbol	Label	Rating or detail	Conductors feeding it
Utility source	Utility service	120/240V 1φ 3W
Meter	Utility meter	200A socket	Service conductors, per utility
Circuit breaker	200A 2P	Main breaker
Panel	Main panel	200A bus · 120/240V
Circuit breaker	Existing	Branch breakers
Load	Existing loads
Circuit breaker	40A 2P	PV backfeed, opposite end from main
Disconnect switch	AC disconnect	60A non-fused, lockable, visible blade	3 #8 Cu + #10 G
Inverter	String inverter	7.6 kW · 240V · 32A, integrated DC disconnect
Device	Rapid shutdown (RSD)	Module-level devices	PV wire #10 Cu, 2 strings
PV array	PV array	20 × 400W = 8.0 kW DC

Notes on the sheet

Busbar check: 200A bus × 120% = 240A ≥ 200A main + 40A PV breaker (NEC 705.12).
PV breaker located at the opposite end of the bus from the main breaker and labelled.
Inverter output 32A × 125% = 40A.
Rapid shutdown per NEC 690.12 (CEC Rule 64-218).

Diagram is schematic and not to scale. Field-verify existing equipment ratings. Ratings and conductor sizes shown are typical. Confirm against the adopted code, the equipment listing and a load calculation before installation. Code references are to the 2023 NEC and the 2024 Canadian Electrical Code: see references and editions.