Compare Generators Side-by-Side
Select up to 4 generators to compare specs, power output, noise levels, runtime and more. Your compare URL is shareable.
- Firman T04073
- Cat RP12000 E
Quick charts
Each chart uses its own Y-axis scale (so numbers are comparable within a chart).
Running watts
W
Starting watts
W
Noise
dB
Runtime @50%
h
Running watts by fuel
Shows how output changes across gasoline/propane/natural gas (when available).
| Specification | Firman T04073 | Cat RP12000 E |
|---|---|---|
| General | ||
| Product type | Generator | Generator |
| Fuel | Tri-Fuel | Gasoline |
| Inverter | No | No |
| Parallel capable | No | No |
| RV ready | No | Yes |
| Running watts | 4000 W | Winner: Winner: 12000 W |
| Starting watts | 5000 W | Winner: Winner: 15000 W |
| Noise (lower limit) | Winner: Winner: 67 dB | 0 dB |
| Weight | Winner: Winner: 123.4 lbs | 350 lbs |
| Run time @50% load | Winner: Winner: 12 h | 11.7 h |
| Run time @25% load | 14 h | Not available |
| Fuel tank | 5 gal | 13.2 gal |
| Fuel gauge | Yes | Yes |
| Approx. dimensions (L × W × H) | 29.8 x 27.5 x 26.1 | 35.7 x 32.7 x 35.8 |
| Electrical | ||
| Voltage (AC) | 120/240 | 120/240 |
| Voltage (DC) | Not available | 12 |
| GFCI outlets | Yes | Yes |
| Covered outlets | Yes | Yes |
| Automatic Voltage Regulation | Yes | Yes |
| THD | 11%-14% % | 5 % |
| Engine | ||
| Engine | 223 cc OHV 4-stroke, cast iron sleeve | 670 cc Rato OHV V-Twin |
| Alternator | Not available | Not available |
| Starting system | Recoil, Electric | Electric |
| Warranty | ||
| Warranty | 3 years | 2 years |
| Power by fuel | ||
| Gasoline | Not available | Not available |
| Running watts | 4000 W | 12000 W |
| Starting watts | 5000 W | 15000 W |
| Running amps (120V) | Not available | Not available |
| Running amps (240V) | Not available | Not available |
| Peak amps (120V) | Not available | Not available |
| Peak amps (240V) | Not available | Not available |
| Run time @50% load | 14 h | 11.7 h |
| Run time @25% load | Not available | Not available |
| Natural gas | Not available | Not available |
| Running watts | 3200 W | Not available |
| Starting watts | 4000 W | Not available |
| Running amps (120V) | Not available | Not available |
| Running amps (240V) | Not available | Not available |
| Peak amps (120V) | Not available | Not available |
| Peak amps (240V) | Not available | Not available |
| Run time @50% load | Not available | Not available |
| Run time @25% load | Not available | Not available |
| Propane | Not available | Not available |
| Running watts | 3600 W | Not available |
| Starting watts | 4500 W | Not available |
| Running amps (120V) | Not available | Not available |
| Running amps (240V) | Not available | Not available |
| Peak amps (120V) | Not available | Not available |
| Peak amps (240V) | Not available | Not available |
| Run time @50% load | 9 h | Not available |
| Run time @25% load | Not available | Not available |
| Other | ||
| Data center | Not available | Not available |
| Indicators | true | false |
| Compliance | CARB, EPA, ANSI/PGMA G300-2023 | CARB, EPA |
| Security | Not available | Not available |
| Spark arrestor | Yes | Yes |
| Neutral | true | true |
| UPC | 840876140734 | 815683023891 |
| Core / High-priority specs | ||
| Running Watts (Gasoline) | 4000 | 12000 |
| Running Watts (Propane) | 3600 | Not available |
| Running Watts (Natural Gas) | 3200 | Not available |
| Starting Watts (Gasoline) | 5000 | 15000 |
| Starting Watts (Propane) | 4500 | Not available |
| Starting Watts (Natural Gas) | 4000 | Not available |
| Runtime @ 50% Load (Gasoline) | 14 | 11.7 |
| Runtime @ 50% Load (Propane) | 9 | Not available |
| AC Outlet Types | 1x Duplex 120V 20A (5-20R) GFCI; 1x 120V 30A (L5-30R); 1x 120/240V 30A (L14-30R) | 2x Duplex 120V 20A (5-20R) GFCI; 2x 120V 30A (L5-30R); 1x 120/240V 30A (L14-30R); 1x 120/240V 50A (14-50R) |
| Electrical & power | ||
| Frequency | 60 | 60 |
| Engine & construction | ||
| Engine Type | 223 cc OHV 4-stroke | 670 cc Rato OHV V-Twin |
| Engine Displacement | 223 | 670 |
| Cylinder Sleeve | cast iron | Not available |
| Runtime & fuel system | ||
| Runtime @ 50% Load (Gasoline) | 14 | 11.7 |
| Runtime @ 50% Load (Propane) | 9 | Not available |
| Safety & compliance | ||
| Overload Protection System | Low oil and overload protection, CO monitoring | Low oil and overload protection |
| Low Oil Protection | Yes | Yes |
| Carbon Monoxide Monitoring | Yes | No |
| Included equipment | ||
| Starting Components | Recoil, Electric | Battery, Battery Charger, Wheel Kit |
| Included Accessories | Oil, funnel, tool kit, propane hose, RV adapter, cover, battery, and wheel kit | Oil, funnel, tool kit, battery charger, battery, and wheel kit |
| Warranty & identification | ||
| Commercial Warranty | 3 | Not available |
| Part Number | Not available | 502-3700 |
| Additional specs | ||
| Summary | The Firman T04073 is a 4,000-watt tri-fuel generator that runs on gasoline, propane, or natural gas. On gasoline, it delivers 5,000 starting watts and 4,000 running watts, enough to power a refrigerator, microwave, and multiple household circuits simultaneously. On propane, output drops to 3,600 running watts, and on natural gas it falls to 3,200 running watts. This fuel flexibility means users can switch between sources based on availability and cost, a significant advantage during extended outages or in remote locations where one fuel type may be scarce.
The T04073 targets homeowners, RV owners, and job site operators who need reliable backup power without the commitment to a single fuel source. Its 5-gallon tank runs for 14 hours at 25% load on gasoline, translating to roughly one week of emergency backup if you run it a few hours per day. The unit includes a wheel kit, making it easier to position despite its 123.4-pound weight. | The Cat RP12000 E is a 12,000-watt gasoline generator built for job sites, construction crews, and homeowners who need sustained power for multiple heavy tools or appliances simultaneously. The 15,000-watt peak output handles startup surges from air compressors, circular saws, and welders without stalling. At 350 pounds, this is a stationary or semi-portable unit. It ships with a wheel kit, battery charger, and full tool set, meaning users can operate it immediately without additional purchases. |
- Most PowerfulCat RP12000 E12000W running
- QuietestFirman T0407367 dB
- Longest RuntimeFirman T0407312h at 50% load
Where to buy
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Firman T04073
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Cat RP12000 E
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