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.
- Yamaha EF3000iS
- Cat RP5500
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 | Yamaha EF3000iS | Cat RP5500 |
|---|---|---|
| General | ||
| Product type | Generator | Generator |
| Fuel | Gasoline | Gasoline |
| Inverter | Yes | No |
| Parallel capable | No | No |
| RV ready | No | No |
| Running watts | 2800 W | Winner: Winner: 5500 W |
| Starting watts | 3000 W | Winner: Winner: 6875 W |
| Noise (lower limit) | Winner: Winner: 54.5 dB | 0 dB |
| Weight | Winner: Winner: 136 lbs | 178 lbs |
| Run time @50% load | Not available | Winner: Winner: 15 h |
| Run time @25% load | 18.6 h | Not available |
| Fuel tank | 3.4 gal | 7.9 gal |
| Fuel gauge | Yes | Yes |
| Approx. dimensions (L × W × H) | 26.8 x 17.5 x 21.9 | 32.9 x 27.4 x 24.7 |
| Electrical | ||
| Voltage (AC) | 120 | 120/240 |
| Voltage (DC) | Not available | Not available |
| GFCI outlets | No | Yes |
| Covered outlets | No | Yes |
| Automatic Voltage Regulation | Yes | Yes |
| THD | Not available | Not available |
| Engine | ||
| Engine | 171 cc Yamaha MZ175 OHV 4-stroke | 300 cc OHV 4-stroke |
| Alternator | Not available | Not available |
| Starting system | Recoil | Recoil |
| Warranty | ||
| Warranty | 3 years | 2 years |
| Power by fuel | ||
| Gasoline | Not available | Not available |
| Running watts | 2800 W | 5500 W |
| Starting watts | 3000 W | 6875 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 | Not available | 15 h |
| Run time @25% load | 18.6 h | Not available |
| Other | ||
| Data center | Not available | Not available |
| Indicators | true | false |
| Compliance | CARB, EPA | CARB, EPA |
| Security | Not available | Not available |
| Spark arrestor | Yes | Yes |
| Neutral | Floating | Not available |
| UPC | 810856030645 | 815683020036 |
| Core / High-priority specs | ||
| Running Watts (Gasoline) | 2800 | 5500 |
| Starting Watts (Gasoline) | 3000 | 6875 |
| Runtime @ 50% Load (Gasoline) | Not available | 15 |
| Runtime @ 25% Load (Gasoline) | 18.6 | Not available |
| AC Outlet Types | AC outlets1x Duplex 120V 20A (5-20R)1x 120V 30A (L5-30R) | 2x Duplex 120V 20A (5-20R) GFCI, 1x 120/240V 30A (L14-30R) |
| Electrical & power | ||
| Frequency | 60 | 60 |
| Engine & construction | ||
| Engine Type | Yamaha MZ175 OHV 4-stroke | OHV 4-stroke |
| Engine Displacement | 171 | 300 |
| Engine Oil Type | Not available | SAE 30 or 10W-30 |
| Runtime & fuel system | ||
| Runtime @ 25% Load (Gasoline) | 18.6 | Not available |
| Runtime @ 50% Load (Gasoline) | Not available | 15 |
| Safety & compliance | ||
| Overload Protection System | Low oil and overload protection | Low oil and overload protection |
| Low Oil Protection | Yes | Yes |
| Carbon Monoxide Monitoring | Yes | No |
| Included equipment | ||
| Included Accessories | Battery charging cables | Oil, funnel, tool kit, and wheel kit |
| Warranty & identification | ||
| Commercial Warranty | 3 | Not available |
| Part Number | Not available | 502-3686 |
| Additional specs | ||
| Summary | The Yamaha EF3000iS is a 3000-watt inverter generator designed for quiet operation and portability, featuring advanced technologies like Smart Throttle and Noise Block, and backed by a 3-year limited warranty. | The Cat RP5500 is a 5500-watt gasoline generator built for homeowners, contractors, and outdoor enthusiasts who need reliable backup power without the complexity of larger units. This wattage tier handles most household circuits simultaneously, meaning you can run a refrigerator, well pump, and power tools at the same time, but not your entire home's air conditioning system. The 6875-watt peak capacity gives it the muscle to start high-inrush devices like compressors and sump pumps without stalling. Because the RP5500 runs on gasoline, fuel is available at any gas station, eliminating the supply chain friction of propane or diesel models. The 7.9-gallon tank paired with 15-hour runtime at half load means you refuel roughly once per day under typical use, not every few hours. |
- Most PowerfulCat RP55005500W running
- QuietestYamaha EF3000iS54.5 dB
- Longest RuntimeCat RP550015h at 50% load
Where to buy
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Yamaha EF3000iS
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Cat RP5500
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