Overview#
The Caterpillar 3412 is a diesel generator built on the 3412C TA -- a 27.02-liter, 12-cylinder V12 engine that extended Cat's 3400 Series architecture to higher power. Available in ratings from 680 kVA to 900 kVA, the 3412C was a staple of large commercial and industrial power generation from its introduction through the 2000s. Though now classified as a legacy product, it remains widely deployed across hospital complexes, university campuses, and heavy industrial sites where its robust construction and proven reliability support continued investment in maintenance and parts.
The 3412C uses an ADEM A5 electronic governor with a pump-and-lines fuel injection system, a step up from the hydra-mechanical governor of the earlier 3412 but without the fully electronic unit injection of modern ACERT models. The generator set accepts 100% rated load in one step per NFPA 110 and meets ISO 8528-5 transient response requirements. The EMCP 4 controller supports optional EMCP 4.2, 4.3, and 4.4 upgrades for facilities requiring advanced metering, relay protection, or paralleling capability.
The 3412C supports 4160V medium-voltage output in addition to standard utilization voltages, and its NFPA 110 Level 1 rating makes it code-compliant for life-safety applications.
Technical Specifications#
| Parameter | Value |
|---|---|
| Minimum rating | 680 kVA |
| Maximum rating | 900 kVA |
| Frequency | 50 or 60 Hz |
| Speed | 1500 or 1800 rpm |
| Voltage | 208V to 600V (4160V option) |
| Engine model | Cat 3412C TA |
| Displacement | 27.02 L (1,649 in³) |
| Bore x stroke | 137.2 mm x 152.4 mm (5.4 in x 6.0 in) |
| Compression ratio | 13:1 |
| Aspiration | Turbocharged-aftercooled |
| Fuel system | Pump and lines |
| Governor | ADEM A5 |
| Fuel consumption @ 100% (648 ekW prime) | 45.3 gal/hr (171.5 L/hr) |
| Fuel consumption @ 75% (648 ekW prime) | 34.4 gal/hr (130.2 L/hr) |
| Fuel consumption @ 50% (648 ekW prime) | 23.9 gal/hr (90.7 L/hr) |
| Motor starting @ 30% voltage dip | 1,629 skVA |
| Alternator frame | 598 |
| Controller | EMCP 4 (4.2/4.3/4.4 optional) |
Our Service Experience#
Our team has extensive experience servicing 3412C units across legacy hospital and campus installations in the South Bay. These engines are workhorses with very long potential service lives, but finding specialty injector and governor components requires lead time. We maintain parts relationships with Cat dealers and key aftermarket suppliers to keep 3412 fleets running reliably.
The V12 configuration requires balanced attention to both cylinder banks during routine inspections -- particularly turbocharger condition, valve adjustment, and fuel injection timing. We always advise clients to stock critical wear items on-site given the legacy parts supply chain. For facilities evaluating upgrade economics, we can compare 3412C life-extension costs against a C27 or C32 ACERT replacement on a net-present-value basis.
Frequently Asked Questions#
What are the power ratings for the Caterpillar 3412 generator? The Cat 3412C generator set is rated from 680 kVA to 900 kVA (544-720 ekW) across 50 Hz and 60 Hz configurations.
What engine does the 3412 generator use? The 3412C TA -- a 27.02-liter V12, four-stroke diesel with a 137.2 mm bore, 152.4 mm stroke, 13:1 compression, and ADEM A5 electronic governor.
What is the fuel consumption of the Cat 3412 generator? At the 648 ekW prime rating, the 3412C consumes 45.3 gal/hr at 100% load, 34.4 gal/hr at 75% load, and 23.9 gal/hr at 50% load.
Is the Caterpillar 3412 still supported by Cat dealers? The 3412C is a legacy product. Parts are available through dealers and aftermarket suppliers, but factory engineering support is limited. We recommend evaluating a C27 upgrade for new installations.
Can the 3412 be paralleled with other units? Yes. The 3412C supports paralleling configurations and has been widely deployed in multi-unit arrays for campus and industrial redundancy applications.
