NTA855 vs KTA19 vs KTA38 vs KTA50: Complete Cummins Generator Engine Comparison
Four engine platforms. One decision. This guide compares official Cummins specifications — power ratings, fuel consumption, weights, dimensions, and total cost of ownership — to help you select the right CCEC generator engine for your project.
Quick Comparison Summary
If you are short on time, here is the headline. All figures below are for the representative 50 Hz / 1500 rpm generator-drive variant of each series, sourced from official Cummins specification sheets.
| Parameter | NTA855-G4 | KTA19-G4 | KTA38-G2 | KTA50-G3 |
|---|---|---|---|---|
| Prime Power (kWe / kVA) | 292 / 365 | 400 / 500 | ~610 / 760 | 1028 / 1285 |
| Standby Power (kWe / kVA) | 320 / 400 | 440 / 550 | ~670 / 840 | 1141 / 1426 |
| Displacement | 14.0 L | 18.9 L | 37.8 L | 50.3 L |
| Cylinders | 6 inline | 6 inline | 12 Vee | 16 Vee |
| Dry Weight | 1,410 kg | 2,200 kg | ~3,950 kg | ~5,200 kg |
| Fuel at 75% Prime | 57 L/h | 82 L/h | ~105 L/h | 199 L/h |
| Engine Series Page | NTA855 → | KTA19 → | KTA38 → | KTA50 → |
Why These Four Engines?
Choosing a generator engine is not just about matching a kilowatt number. The engine platform determines fuel economy, maintenance intervals, spare parts availability, resale value, and physical footprint — all factors that compound over a 15- to 20-year service life.
The NTA855, KTA19, KTA38, and KTA50 are the four pillars of the CCEC (Chongqing Cummins Engine Company) heavy-duty generator-drive lineup. Together they cover roughly 250 kVA to 1,500 kVA — the sweet spot for commercial standby, prime power, mining, marine, and industrial applications across Africa, the Middle East, Southeast Asia, and Latin America.
All four share the same fundamental architecture: four-stroke diesel, turbocharged (with aftercooling on the K-series), Cummins PT fuel system, and replaceable wet cylinder liners. But there are critical differences in displacement, cylinder count, cooling system design, and power density that directly affect your total cost of ownership.
Engine-by-Engine Overview
Cummins NTA855 Entry-Level Workhorse
The NTA855 is the most widely deployed Cummins heavy-duty engine in the developing world. It is a 14-liter inline-six with a decades-long service record in generator sets, construction equipment, marine propulsion, and pump drives. The “-G4” variant is the fuel-optimized generator-drive version, producing 292 kWe prime / 320 kWe standby at 1500 rpm (50 Hz).
What makes the NTA855 enduringly popular is its simplicity: mechanical PT fuel injection, no electronics to fail in harsh environments, and a global spare parts network that even third-party manufacturers support. If you need 250–400 kVA and want the lowest possible maintenance complexity, this is your engine. Browse the full model range on the NTA855 generator engines page, or jump to the NTA855-G4 specific model.
Cummins KTA19 Mid-Range Champion
The KTA19 takes the same inline-six architecture and scales it up: 159 mm bore and stroke (versus 140 × 152 mm on the NTA855), yielding 18.9 liters of displacement. The KTA19-G4 delivers 400 kWe prime / 440 kWe standby at 50 Hz, with a 60 Hz variant reaching 455 kWe prime.
It adds an aftercooler for denser intake charge and more efficient combustion, and Cummins’ Step Timing Control (STC) optimizes injection timing across load conditions. The KTA19 is widely considered the most robust and cost-effective diesel in its power band. It is the natural choice for 400–600 kVA generator sets in commercial buildings, hospitals, and small industrial facilities. See all variants on the KTA19 generator engines page or the KTA19-G4 model page.
Cummins KTA38 Industrial V12
The KTA38 is where the platform shifts from inline-six to a 60-degree V12, doubling the cylinder count to 12 and the displacement to 37.8 liters. The KTA38-G2 produces approximately 610 kWe prime / 670 kWe standby, while higher-tuned variants like the KTA38-G5 reach up to 1,000 kWe. The broader KTA38 series spans 720–928 kW (900–1,160 kVA) prime and 800–1,020 kW (1,000–1,276 kVA) standby across its model range.
The V12 configuration delivers inherently smoother operation and higher power density than two inline-six engines, while sharing bore, stroke, and many components with the KTA19 — simplifying spare parts inventory for fleets that standardize on the K-platform. It is the engine of choice for mining operations, data centers, large commercial standby, and prime power in remote locations. Explore the lineup on the KTA38 generator engines page or the KTA38-G2 model page.
Cummins KTA50 Flagship V16
The KTA50 is the largest and most powerful engine in the CCEC generator-drive lineup. It uses a 60-degree V16 block with 50.3 liters of displacement, and the KTA50-G3 produces 1,028 kWe prime / 1,141 kWe standby at 50 Hz. At 60 Hz, prime output rises to 1,123 kWe. The KTA50 series extends to 1,286 kWe standby across higher-tuned variants like the GS8 and G9.
It features a one-pump, two-loop cooling system (separate circuits for the engine jacket and aftercooler), dual Ni-resist pistons, and nitride-coated intake valves for extreme durability. The KTA50 is engineered for mission-critical installations where downtime is not an option: large data centers, hospitals, airports, mining camps, and offshore platforms. View all models on the KTA50 generator engines page or the KTA50-G3 model page.
Detailed Specifications Table
The following tables consolidate data from official Cummins specification sheets (NTA855-G4, KTA19-G4, KTA50-G3) and CCEC-published data for the KTA38-G2. All values are for the bare engine at 1500 rpm / 50 Hz unless noted.
Power Ratings
| Rating | NTA855-G4 | KTA19-G4 | KTA38-G2 | KTA50-G3 |
|---|---|---|---|---|
| Gross Standby (kWm / BHP) | 351 / 471 | 504 / 675 | 731 / 994 | 1227 / 1645 |
| Gross Prime (kWm / BHP) | 317 / 425 | 448 / 600 | 664 / 903 | 1097 / 1470 |
| Gross Continuous (kWm / BHP) | 272 / 365 | 355 / 475 | — | 900 / 1206 |
| Gen Set Standby (kWe / kVA) | 320 / 400 | 440 / 550 | ~670 / 840 | 1141 / 1426 |
| Gen Set Prime (kWe / kVA) | 292 / 365 | 400 / 500 | ~610 / 760 | 1028 / 1285 |
| Gen Set Continuous (kWe / kVA) | 245 / 306 | 317 / 396 | — | 839 / 1048 |
Note: Generator set ratings account for alternator efficiency and cooling fan losses, which is why they are lower than gross engine output. KTA38-G2 gen set figures are estimated from CCEC engine data at ~92% alternator efficiency; actual ratings vary by alternator and radiator selection.
Mechanical Specifications
| Specification | NTA855-G4 | KTA19-G4 | KTA38-G2 | KTA50-G3 |
|---|---|---|---|---|
| Engine Type | 4-cycle, inline, turbocharged | 4-cycle, inline, turbo & aftercooled | 4-cycle, Vee 60°, turbocharged | 4-cycle, Vee 60°, turbo & aftercooled |
| Bore × Stroke | 140 × 152 mm | 159 × 159 mm | 159 × 159 mm | 159 × 159 mm |
| Displacement | 14.0 L (855 in³) | 18.9 L (1,150 in³) | 37.8 L (2,306 in³) | 50.3 L (3,067 in³) |
| Compression Ratio | — | 13.9 : 1 | 15.5 : 1 | 13.9 : 1 |
| Fuel System | Cummins PT, direct injection | Cummins PT, direct injection | Cummins PT, direct injection | Cummins PT, direct injection |
| Aspiration | Turbocharged | Turbocharged + aftercooled (JWAC) | Turbocharged | Turbocharged + low-temp aftercooler |
| Lube Oil Capacity | 38.6 L | 50 L | ~100 L | 177 L |
| Coolant Capacity | 45.0 L | 93 L (Coolpac total) | — | 152 L |
| Starting Voltage | 24V | 24V | 24V | 24V |
| Flywheel Housing | SAE 1/14 | SAE 0 | SAE 0 | SAE 0 |
Fuel Consumption Deep Dive
Fuel is the single largest operating expense for any generator set — typically 70–80% of total lifetime cost. The data below comes directly from official Cummins spec sheets, measured at 1500 rpm / 50 Hz under ISO 3046 reference conditions.
| Load Point | NTA855-G4 | KTA19-G4 | KTA38-G2* | KTA50-G3 |
|---|---|---|---|---|
| Standby 100% | 84 | 121 | ~155 | 293 |
| Prime 100% | 76 | 107 | ~140 | 261 |
| Prime 75% | 57 | 82 | ~105 | 199 |
| Prime 50% | 39 | 57 | ~72 | 139 |
| Prime 25% | 21 | 30 | ~40 | 76 |
| Continuous 100% | 65 | 86 | — | — |
*KTA38-G2 100% figure from CCEC-published data (140 L/h at 664 kWm prime). 75%, 50%, and 25% values are estimated using typical diesel generator fuel-curve ratios; verify with factory data for your specific model. NTA855, KTA19, and KTA50 figures are from official Cummins PDF spec sheets.
Brake-Specific Fuel Consumption (BSFC)
BSFC measures fuel burned per unit of power produced — the fairest efficiency comparison across different-sized engines. Lower is better.
BSFC at 75% Prime Load (g/kWh)
Annual Fuel Cost Estimate
Assuming 2,000 operating hours per year at 75% prime load and a diesel price of USD $1.00 per liter:
| Engine | L/h at 75% | Liters/year | Annual fuel cost | Cost per kWh |
|---|---|---|---|---|
| NTA855-G4 | 57 | 114,000 | $114,000 | $0.240 |
| KTA19-G4 | 82 | 164,000 | $164,000 | $0.244 |
| KTA38-G2 | ~105 | 210,000 | $210,000 | $0.211 |
| KTA50-G3 | 199 | 398,000 | $398,000 | $0.242 |
At higher diesel prices — common in remote areas and island nations — multiply proportionally. At $1.50/L, the KTA50 burns nearly $600,000 per year in fuel. This is why right-sizing the engine to your actual load profile is the single most important cost decision you will make.
Weight, Dimensions & Installation
Engine weight and dimensions affect foundation design, containerized enclosure selection, shipping cost, and rigging requirements. The figures below are for the bare engine (dry weight); a complete open-type generator set with alternator, radiator, base tank, and control panel typically weighs 2.5–3.5× the engine alone.
| Engine | Dry Weight | Length | Width | Height | Complete Genset Weight (approx.) |
|---|---|---|---|---|---|
| NTA855-G4 | 1,410 kg | 2,055 mm | 990 mm | 1,535 mm | ~3,500–4,000 kg |
| KTA19-G4 | 2,200 kg | 2,600 mm | 1,344 mm | 1,773 mm | ~4,000–4,500 kg |
| KTA38-G2 | ~3,950 kg | 2,341 mm | 1,360 mm | 1,653 mm | ~7,500–8,500 kg |
| KTA50-G3 | ~5,200 kg | 2,794 mm | 1,507 mm | 1,846 mm | ~9,000–10,500 kg |
Practical Installation Notes
- NTA855 and KTA19 both fit in a 20-foot container as open-type generator sets. The KTA19’s greater width (1,344 mm) leaves less side clearance for maintenance.
- KTA38 requires a 20-foot high-cube or 40-foot container, and its V12 configuration needs careful exhaust manifold routing — the two banks require separate turbocharger piping.
- KTA50 demands a 40-foot container or dedicated plant room. Its 177-liter lubrication system means oil changes require a dedicated drain and refill system, not a manual pump.
- All four engines use SAE 0 (or SAE 1/14 on the NTA855) flywheel housings, which are industry-standard and compatible with major alternator brands including Stamford, Leroy-Somer, and Marathon.
- For high-ambient installations (above 40 °C), all models require derating. The NTA855-G4 Coolpac is rated to 54.7 °C, while the KTA19-G4 is limited to 50 °C ambient.
Which Engine Do You Need?
Use this power ladder to narrow your choice based on your required prime kVA. The most common sizing mistake is buying too much engine — generators run most efficiently at 70–80% load, and running below 30% causes carbon buildup (wet stacking) that shortens engine life.
By Application
| Application | Recommended Series | Why |
|---|---|---|
| Standby for commercial building | NTA855 or KTA19 | Low running hours; simplicity and parts availability matter more than peak efficiency |
| Prime power — remote site | KTA19 or KTA38 | Fuel economy at sustained load; KTA38 wins above 600 kVA |
| Data center standby | KTA38 or KTA50 | N+1 redundancy, instant load acceptance, long TBO (time between overhaul) |
| Mining / construction | KTA38 or KTA50 | High ambient tolerance, mechanical PT fuel system survives dust and vibration |
| Hospital / critical facility | KTA19 + redundant unit | Two 500 kVA units provide redundancy that one 1,000 kVA cannot |
| Telecom / tower | NTA855 | Low load but high reliability; proven in millions of installations worldwide |
| Marine auxiliary | NTA855-D(M) / KTA19-D(M) | Marine-certified variants with heat exchanger cooling; see marine engine lineup |
Bottom Line
If your actual running load is under 320 kWe, the NTA855 will cost less to buy, less to maintain, and is easier to service in remote locations. The KTA19 is the sweet spot for 320–400 kWe prime. The KTA38 offers the best fuel efficiency per kWh above 500 kWe. The KTA50 is the only choice when a single engine must deliver over 900 kWe — but consider two smaller units for redundancy unless space is the deciding factor.
Cost of Ownership
Engine purchase price is only 15–25% of total lifetime cost. Fuel dominates, followed by maintenance, overhaul, and financing. The ranges below are indicative market prices for CCEC-built engines (FOB China) and will vary by configuration, alternator brand, controller, and enclosure type.
| Engine | Engine Only | Complete Open Genset | Overhaul Interval | Major Overhaul Cost (est.) |
|---|---|---|---|---|
| NTA855-G4 | $45,000–$85,000 | $60,000–$110,000 | 12,000–15,000 h | $8,000–$15,000 |
| KTA19-G4 | $75,000–$130,000 | $100,000–$170,000 | 12,000–15,000 h | $12,000–$22,000 |
| KTA38-G2 | $160,000–$280,000 | $200,000–$350,000 | 15,000–18,000 h | $25,000–$45,000 |
| KTA50-G3 | $220,000–$380,000 | $280,000–$480,000 | 15,000–20,000 h | $40,000–$70,000 |
Price ranges are market estimates compiled from third-party supplier listings and do not constitute a formal quotation. Contact BLSH Diesel for a configured quote based on your exact requirements.
What Drives Maintenance Cost
- Oil change intervals: 250–500 hours depending on duty cycle and oil analysis. The NTA855 holds 38.6 L; the KTA50 holds 177 L — a single oil change on the KTA50 uses nearly 5× the lubricant.
- Filter kits: All four use spin-on fuel and lube filters that are inexpensive and globally available. The KTA50 uses dual fuel filters and a bypass oil filter, adding to per-service cost.
- Cylinder liners: All four have replaceable wet liners, which means a major overhaul does not require re-boring the block — a significant cost advantage over parent-bore engines.
- Turbocharger: Holset/Cummins Turbo Technologies units are standard across the range. The KTA50 uses dual turbochargers (one per bank).
- Genuine parts: CCEC-built engines use the same part numbers as global Cummins engines, and genuine Cummins parts are available through the worldwide distributor network.
Frequently Asked Questions
Q: What is the difference between NTA855, KTA19, KTA38, and KTA50 engines?
The primary difference is displacement and cylinder count. The NTA855 is a 14-liter inline-six (292 kWe prime), the KTA19 is an 18.9-liter inline-six (400 kWe prime), the KTA38 is a 37.8-liter V12 (~610 kWe prime), and the KTA50 is a 50.3-liter V16 (1,028 kWe prime). All use Cummins PT mechanical fuel injection and are manufactured by CCEC in Chongqing, China. The K-series engines (KTA19/38/50) feature aftercooling and heavier-duty components than the NTA855.
Q: Which Cummins generator engine is the most fuel efficient?
Among these four, the KTA38 has the best brake-specific fuel consumption at approximately 176 g/kWh at 75% load, compared to 199–203 g/kWh for the other three. Larger V-configuration engines benefit from better thermal efficiency. However, real-world fuel economy depends heavily on proper load matching — a KTA50 running at 25% load will burn more fuel per kWh than a correctly sized NTA855 running at 75%.
Q: How much fuel does a Cummins diesel generator use per hour?
At 75% prime load (the most efficient operating point), an NTA855-G4 uses approximately 57 L/h, a KTA19-G4 uses 82 L/h, a KTA38-G2 uses about 105 L/h, and a KTA50-G3 uses 199 L/h. At full prime load, consumption rises to 76, 107, 140, and 261 L/h respectively. Always size the generator so your typical running load falls in the 70–80% range.
Q: What does KTA stand for in Cummins engines?
In Cummins nomenclature, “K” refers to the K-series engine platform, “T” stands for turbocharged, and “A” stands for aftercooled. So KTA = K-series, Turbocharged, Aftercooled. The NTA855 follows the same pattern: N-series, Turbocharged, Aftercooled, with 855 cubic inches of displacement. The “Q” prefix (as in QSK19) denotes the Quantum series with electronic fuel injection.
Q: How long do Cummins generator engines last before overhaul?
With proper maintenance and operation at recommended load factors, CCEC K-series engines typically achieve 12,000–20,000 hours between major overhauls. The NTA855 and KTA19 generally reach 12,000–15,000 hours, while the larger KTA38 and KTA50 can reach 15,000–20,000 hours due to their heavier construction. Standby applications (low running hours with regular exercise) can see 20+ years of service before overhaul is needed.
Q: What is the difference between prime, standby, and continuous power ratings?
Per ISO 8528: Standby (ESP) is for emergency use during utility outages with no overload capability. Prime (PRP) is for unlimited hours at varying load, with a 10% overload capability available for one hour in twelve. Continuous (COP) is for unlimited hours at a constant, non-varying load. Prime ratings are typically 10–15% higher than continuous ratings on the same engine.
Q: Where are CCEC Cummins engines manufactured?
CCEC (Chongqing Cummins Engine Company Ltd.) is a joint venture between Cummins Inc. and Chongqing Machinery & Electronics Group, established in 1995. The factory is in Chongqing, China, and produces the NTA855, KTA19, KTA38, KTA50, QSK19, and M11 series engines to Cummins global quality standards (ISO 9001 certified). CCEC engines are identical in specification and parts interchangeability to equivalent models produced at other Cummins facilities worldwide.
Q: How much does a Cummins NTA855 / KTA19 / KTA38 / KTA50 engine weigh?
Dry engine-only weights are approximately: NTA855-G4 at 1,410 kg, KTA19-G4 at 2,200 kg, KTA38-G2 at about 3,950 kg, and KTA50-G3 at about 5,200 kg. Complete generator sets (with alternator, radiator, base frame, and controls) weigh roughly 2.5–3.5 times the bare engine, ranging from about 3,500 kg for an NTA855 genset to over 10,000 kg for a KTA50 genset.
Need Help Selecting the Right Engine?
BLSH Diesel supplies genuine CCEC Cummins generator engines and complete generator sets to customers in over 40 countries. Send us your load requirements and we will recommend the right engine — no oversizing, no guesswork.
Request a QuotationData Sources
- Cummins NTA855-G4 Official Specification Sheet (PDF)
- Cummins KTA19-G4 Fuel Optimized Specification Sheet (PDF)
- Cummins KTA50-G3 Official Specification Sheet (PDF)
- Cummins QSK19-G4 Specification Sheet (PDF)
- Cummins KTA19 Series Product Page — cummins.com
- Cummins NTA855 Generator Product Page — cummins.com
- ISO 8528-1: Reciprocating internal combustion engine driven alternating current generating sets — definitions and ratings.
