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  • Cummins Onan P9500DF EFI
  • Cat RP5500
  • Model Onan P9500DF EFI
    Model Onan P9500DF EFI

    Cummins 7,500W Dual-Fuel Generator

    7500W
    Running
    74 dB
    Noise
    View details
  • Model RP5500
    Model RP5500

    Cat 5,500W Gas Generator

    5500W
    Running
    0 dB
    Noise
    View details
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).
Generator Specifications Comparison
SpecificationCummins Onan P9500DF EFICat RP5500
General
Product type
Generator
Generator
Fuel
Dual-Fuel
Gasoline
InverterNoNo
Parallel capableNoNo
RV readyNoNo
Running watts
Winner: Winner: 7500 W
5500 W
Starting watts
Winner: Winner: 9500 W
6875 W
Noise (lower limit)
Winner: Winner: 74 dB
0 dB
Weight
211.6 lbs
Winner: Winner: 178 lbs
Run time @50% load
9.6 h
Winner: Winner: 15 h
Run time @25% load
14.4 h
Not available
Fuel tank
6.6 gal
7.9 gal
Fuel gaugeYesYes
Approx. dimensions (L × W × H)
27.3 x 20.6 x 22.6
32.9 x 27.4 x 24.7
Electrical
Voltage (AC)
120/240
120/240
Voltage (DC)
5
Not available
GFCI outletsYesYes
Covered outletsYesYes
Automatic Voltage RegulationYesYes
THD
23 %
Not available
Engine
Engine
420 cc OHV 4-stroke
300 cc OHV 4-stroke
Alternator
Not available
Not available
Starting system
Recoil, Electric, Remote
Recoil
Warranty
Warranty
3 years
2 years
Power by fuel
GasolineNot availableNot available
Running watts
7500 W
5500 W
Starting watts
9500 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
9.6 h
15 h
Run time @25% load
14.4 h
Not available
PropaneNot availableNot available
Running watts
6750 W
Not available
Starting watts
8550 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
10.8 h
Not available
Other
Data center
Not available
Not available
Indicators
false
false
Compliance
CARB, EPA, ANSI/PGMA G300-2023
CARB, EPA
Security
Not available
Not available
Spark arrestorYesYes
Neutral
true
Not available
UPC
Not available
815683020036
Core / High-priority specs
Running Watts (Gasoline)
7500
5500
Running Watts (Propane)
6750
Not available
Starting Watts (Gasoline)
9500
6875
Starting Watts (Propane)
8550
Not available
Runtime @ 50% Load (Gasoline)
9.6
15
Runtime @ 25% Load (Gasoline)
14.4
Not available
Runtime @ 25% Load (Propane)
10.8
Not available
AC Outlet Types
2x Duplex 120V 20A (5-20R) GFCI; 1x 120/240V 30A (L14-30R)
2x Duplex 120V 20A (5-20R) GFCI, 1x 120/240V 30A (L14-30R)
Electrical & power
Frequency
60
60
Engine & construction
Engine Type
OHV 4-stroke
OHV 4-stroke
Engine Displacement
420
300
Engine Oil Type
SAE10W30
SAE 30 or 10W-30
Runtime & fuel system
Runtime @ 25% Load (Gasoline)
14.4
Not available
Runtime @ 50% Load (Gasoline)
9.6
15
Safety & compliance
Overload Protection System
Low oil and overload protection
Low oil and overload protection
Low Oil ProtectionYesYes
Carbon Monoxide MonitoringYesNo
Included equipment
Mobility Components
Yes
Not available
Included Accessories
Oil, funnel, tool kit, key fob, propane hose, battery, and wheel kit
Oil, funnel, tool kit, and wheel kit
Warranty & identification
Commercial Warranty
3
Not available
Part Number
A075C509
502-3686
Additional specs
Summary
The Cummins Onan P9500DF EFI is a 7,500-watt dual-fuel generator built for users who need sustained power across multiple load types. On gasoline, it delivers 7,500 running watts and 9,500 peak watts. On propane, it drops to 6,750 running watts and 8,550 peak watts, which means propane users sacrifice roughly 10 percent of output but gain extended storage life and cleaner emissions. The electronic fuel injection engine handles high-altitude operation up to 13,123 feet without modification, making it viable for mountain jobsites, remote cabins, and RV camps where carbureted engines would struggle. At 211.6 pounds with an included wheel kit, this generator demands stationary placement or two-person handling, but the 6.6-gallon fuel tank stretches runtime to 14.4 hours at 25 percent load on gasoline. This is a workhorse for contractors, emergency backup, and off-grid scenarios where fuel flexibility and durability matter more than portability.
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 Powerful
    Cummins Onan P9500DF EFI
    7500W running
  • Quietest
    Cummins Onan P9500DF EFI
    74 dB
  • Longest Runtime
    Cat RP5500
    15h at 50% load
Where to buy
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Cummins Onan P9500DF EFI
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Cat RP5500
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