Template · Solar and storage

Ground-mount PV with feeder to the house single line diagram

Array and inverter in the yard, a 250 ft underground feeder and a backfed breaker in the main panel. Use this for an array on a ground mount some distance from the house, with the inverter at the array and an underground AC feeder back to a breaker in the main panel.

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.

Open this template in the editor Download the SVG

Ground-mount PV with feeder to the house single line diagram: array and inverter in the yard, a 250 ft underground feeder and a backfed breaker in the main panel. — Ground-mount PV with feeder to the house. 12 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 feeder size against voltage drop, the equipment grounding conductor increased with it, a disconnect at the array and one at the house, the busbar arithmetic, and how the array structure is grounded.

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	Branch breakers
To (continues off sheet)	To house loads
Circuit breaker	40A 2P	PV backfeed, opposite end from main
Disconnect switch	AC disconnect	60A non-fused, lockable, at the house	3 #8 Cu + #10 G
Disconnect switch	Array disconnect	60A · NEMA 3R, at the array	3 #4 Cu + #4 G, underground, 250 ft
Grounding electrode	Ground rods	At the array, #6 Cu GEC
Inverter	String inverter	7.6 kW · 240V · 32A, at the array · DC disconnect
PV array	Ground-mount array	20 × 400W = 8.0 kW DC	PV wire #10 Cu + #10 G, 2 strings

Notes on the sheet

Busbar check: 200A bus × 120% = 240A ≥ 200A main + 40A PV breaker (NEC 705.12). Inverter output 32A × 125% = 40A.
Feeder increased for voltage drop: 32A over 250 ft on #4 Cu is about 2%. Equipment grounding conductor increased in the same proportion (NEC 250.122(B)): 10,380 cmil × 41,740 ÷ 16,510 = 26,242 cmil, just over the 26,240 of a #6, so #4 Cu.
A grounding electrode at the array, connected to the equipment grounding conductor at the array disconnect, with the neutral isolated there. Most AHJs treat the array, with its inverter and disconnect, as a structure supplied by a feeder and require it (NEC 250.32); it is good practice in any case. It does not take the place of the equipment grounding conductor run with the feeder.
The PV circuits stay at the array and enter no building, so rapid shutdown (NEC 690.12) is not called for. Confirm with the AHJ.
Array wiring within reach guarded or in raceway. Burial depth per the adopted code for the wiring method used.

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.