Battery with independent standby generator single line diagram
Generator transfer switch upstream of the battery gateway. Use this where a home has both a standby generator and a battery. The generator’s transfer switch sits upstream of the battery gateway, so the two sources never run in parallel.
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
What the reviewer checks on this drawing
The reviewer checks that the transfer switch is the service disconnect with neutrals isolated downstream, and that the arrangement follows the storage manufacturer’s generator-integration instructions, including whether the battery may charge from the generator.
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 |
| Transfer switch | Automatic transfer switch | 200A · service rated | |
| Circuit breaker | 100A 2P | Generator breaker | |
| Generator | Standby generator | 22 kW · 120/240V | |
| Device | Backup gateway (GATEWAY) | 200A | |
| Panel | Main panel | 200A bus · neutrals isolated | |
| Circuit breaker | Existing | All house loads | |
| Load | Existing loads | ||
| Circuit breaker | 30A 2P | Battery | |
| Battery | AC-coupled battery | 5 kW · 13.5 kWh |
Notes on the sheet
- Generator and battery do not operate in parallel. Follow the ESS manufacturer generator-integration instructions.
- Transfer switch is the service disconnect; neutrals isolated downstream.
- Battery charging from the generator disabled unless the manufacturer permits it.
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.
Related solar and battery drawings
Grid-tied PV, string inverter
Load-side connection through a 40A backfed breaker.
Solar · storageView drawing
Grid-tied PV, microinverters
Two microinverter branches combined in an AC combiner.
Solar · storageView drawing
PV supply-side connection
Line-side tap with a fused, service-rated PV disconnect.
Solar · storageView drawing
PV and storage, hybrid inverter
DC-coupled battery with a backup loads panel.
Solar · storageView drawingSee all solar and battery single line diagrams, or all 40 templates.
Start from this drawing
Free, in the browser, no account. Start from a template or describe the job in plain words, edit the drawing and export a PDF.