Cummins
Cummins QSJ5.9G
QSJ
Cummins QSJ5.9G is a 5.9 L inline-6 spark-ignited natural-gas generator engine. Cummins lists G1, G2 and G3 ratings in EPA NSPS-certified 60 Hz sets from 45 to 100 kWe; EPA annual certification data lists up to 123.8 kWm at 1800 RPM.
- Standby Power · 60 Hz
- 125 kVA
- Electrical Output
- 100 kWe
- Cylinders
- L6
- Displacement
- 5.9 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 | |
|---|---|---|---|
| Standby Power | — | 100 | 125 |
Cummins QSJ5.9G generator set context
The Cummins QSJ5.9G is listed here as a natural gas generator-drive engine for 60 Hz generator sets, with a headline 125 kVA / 100 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.
Also searched as
Technical Specifications
| Brand | Cummins |
| Model | QSJ5.9G |
| Series | QSJ |
| Configuration | L6 Turbocharged Spark Ignition |
| Cylinders | 6 |
| Displacement | 5.9 L |
| Fuel Type | Natural Gas |
| Ignition Type | Spark Ignition |
| Cooling Method | Liquid-Cooled |
| Emissions Standard | U.S. EPA Stationary |
| Certifications | U.S. EPA NSPS |
| Country of Origin | United States |
Frequently asked questions
What is the power output of the Cummins QSJ5.9G?
The Cummins QSJ5.9G is rated at 125 kVA standby at 60 Hz (1,800 rpm).
Does the QSJ5.9G run at 50 Hz or 60 Hz?
The Cummins QSJ5.9G is rated for 60 Hz (1,800 rpm).
What fuel does the Cummins QSJ5.9G use?
The Cummins QSJ5.9G is a Natural Gas generator-set engine.
What is the displacement and cylinder configuration of the QSJ5.9G?
The Cummins QSJ5.9G is an inline-6 (6-cylinder) engine with a displacement of 5.9 L.
What emissions standard does the QSJ5.9G meet?
The Cummins QSJ5.9G is certified to U.S. EPA Stationary emissions standards.
Is the Cummins QSJ5.9G still in production?
Yes — the Cummins QSJ5.9G is a current production model.
Is a datasheet available for the QSJ5.9G?
Yes — an official Cummins datasheet for the Cummins QSJ5.9G can be downloaded from this page.
Related Engines
Compare Cummins QSJ5.9G
Reference
- Canonical page
- /engines/cummins-qsj5-9g
- Last database update
- 2026-07-25
- Manufacturer files
- 1 datasheet linked
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