Overview#
The Caterpillar 3406 is a diesel generator built on the legendary 3406C TA -- a 14.64-liter inline-6 engine that has proven itself across millions of operating hours in trucking, construction, marine, and stationary power applications. The generator set is available in ratings from 275 ekW to 400 ekW across both 50 Hz and 60 Hz configurations, serving commercial standby, industrial, and municipal applications worldwide.
As a legacy platform, the 3406 benefits from one of the broadest parts ecosystems in the diesel industry. The 3406C block was produced in enormous quantities across Cat's heavy equipment, over-the-road truck, and marine programs, which means parts supply is robust and technicians familiar with the engine are widely available. The hydra-mechanical governor and pump-and-lines fuel system are straightforward to service and rebuild without proprietary diagnostic software.
The generator set accepts 100% rated load in one step per NFPA 110 and meets ISO 8528-5 transient response requirements. Standard equipment includes the EMCP 4 controller, package-mounted radiator, 24V electric starting motor, and rubber vibration isolators. Optional sound-attenuated and weather-protective enclosures are available.
Technical Specifications#
| Parameter | Value |
|---|---|
| Minimum rating | 275 ekW |
| Maximum rating | 400 ekW |
| Frequency | 50 or 60 Hz |
| Speed | 1500 or 1800 rpm |
| Engine model | Cat 3406C TA |
| Displacement | 14.64 L (893 in³) |
| Bore x stroke | 137.2 mm x 165.1 mm (5.4 in x 6.5 in) |
| Compression ratio | 14.5:1 |
| Aspiration | Turbocharged-aftercooled |
| Fuel system | Pump and lines |
| Governor | Hydra-mechanical |
| Fuel consumption @ 100% (275 ekW prime) | 21.0 gal/hr (79.6 L/hr) |
| Fuel consumption @ 75% (275 ekW prime) | 16.3 gal/hr (61.6 L/hr) |
| Fuel consumption @ 50% (275 ekW prime) | 11.8 gal/hr (44.7 L/hr) |
| Controller | EMCP 4 (4.2/4.3/4.4 optional) |
| Alternator excitation | AR (standard) or PM (optional) |
Our Service Experience#
The 3406C is one of the most service-friendly engines in the generator market due to the shared parts pool with the heavy-truck and construction equipment markets. Our technicians can source injectors, heads, and governors through Cat dealers and multiple aftermarket channels, which keeps downtime short. The hydra-mechanical governor requires periodic calibration verification -- particularly on standby units that run infrequently -- to ensure load pick-up response within NFPA 110 tolerances.
We work with many municipalities and commercial properties that have 3406-based systems in their critical infrastructure. We recommend a structured PM program including annual load bank testing, semi-annual fuel polishing, and regular battery testing to maximize the remaining service life of these durable machines. For facilities evaluating a platform upgrade, we can conduct a life assessment and provide a cost/benefit analysis comparing continued 3406 maintenance against a C13 or C15 ACERT replacement.
Frequently Asked Questions#
What are the power ratings for the Caterpillar 3406 generator? The Cat 3406C generator set is available from 275 ekW to 400 ekW across 50 Hz and 60 Hz configurations.
What engine does the 3406 generator use? The 3406C TA -- a 14.64-liter inline-6 with a 137.2 mm bore, 165.1 mm stroke, 14.5:1 compression, hydra-mechanical governor, and pump-and-lines fuel system.
What is the fuel consumption of the Cat 3406 generator? At the 275 ekW prime rating (60 Hz, 480V), the 3406C consumes approximately 21.0 gal/hr at 100% load, 16.3 gal/hr at 75% load, and 11.8 gal/hr at 50% load.
Is the 3406 a good choice for a new installation today? The 3406C is a legacy platform with strong parts availability. For new installations, the C13 or C15 ACERT are the modern equivalents with better emissions compliance and digital controls. We support both existing 3406 installations and upgrade assessments.
What applications is the 3406 well-suited for? The 3406C at 275-350 kW is well-matched to commercial buildings, municipal facilities, and industrial sites needing reliable three-phase standby power. Its inline-6 architecture and broad parts availability make it practical to maintain.
