Generac
Generac SG400
Industrial Gaseous
Generac SG400 is a 400 kWe standby and 360 kWe prime industrial gaseous generator using the 21.9 L V12 platform at 1800 RPM. It is EPA certified for stationary emergency and non-emergency service.
Overhaul & repair parts- Manufacturer files
- 1 datasheet
- Last updated
- 2026-07-26
- Package route
- gas generator sets
- Standby Power · 60 Hz
- 500 kVA
- Electrical Output
- 400 kWe
- Cylinders
- V12
- Displacement
- 21.9 L
- Rated Speed
- 1,800 RPM
Power Ratings
kWm = mechanical shaft power · kWe = electrical output · kVA = kWe ÷ 0.8 pf
60 Hz1800 RPM
| kWm | kWe | kVA | |
|---|---|---|---|
| Prime Power | — | 360 | 450 |
| Standby Power | — | 400 | 500 |
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Generac SG400 overhaul & repair parts
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Generac SG400 generator set context
The Generac SG400 is listed here as a natural gas generator-drive engine for 60 Hz generator sets, with a headline 500 kVA / 400 kWe / standby rating. Use this page to compare the published engine output, electrical kWe/kVA ratings, emissions level, datasheet availability, and neighboring models before specifying an alternator, controller, enclosure, voltage, and compliance package.
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Technical Specifications
| Brand | Generac |
| Model | SG400 |
| Series | Industrial Gaseous |
| Configuration | V12 Turbocharged Aftercooled |
| Cylinders | 12 |
| Displacement | 21.9 L |
| Fuel Type | Natural Gas |
| Ignition Type | Spark Ignition |
| Cooling Method | Liquid-Cooled |
| Emissions Standard | U.S. EPA Stationary |
| Certifications | U.S. EPA Stationary, U.S. EPA Stationary Emergency, U.S. EPA Stationary Non-Emergency |
| Country of Origin | United States |
Frequently asked questions
What is the power output of the Generac SG400?
The Generac SG400 is rated at 500 kVA standby / 450 kVA prime at 60 Hz (1,800 rpm).
Does the SG400 run at 50 Hz or 60 Hz?
The Generac SG400 is rated for 60 Hz (1,800 rpm).
What fuel does the Generac SG400 use?
The Generac SG400 is a Natural Gas generator-set engine.
What is the displacement and cylinder configuration of the SG400?
The Generac SG400 is a V12 (12-cylinder) engine with a displacement of 21.9 L.
What emissions information is listed for the SG400?
This record lists U.S. EPA Stationary for the Generac SG400. Confirm the exact engine family, model year, configuration and applicable manufacturer certification documents before specifying it for a regulated project. A database label does not establish certification of a complete generator package.
What is the catalog status of the Generac SG400?
The Generac SG400 is marked active in this database. Confirm current production and availability with the manufacturer; catalog status is not a live supply check.
Are reference documents available for the SG400?
This page links reference documents for the Generac SG400. Check each document's title, model coverage, revision and rating conditions before using it for selection.