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  • Cummins Onan P9500df
  • Cat RP6500 E
  • Model Onan P9500df
    Model Onan P9500df

    Cummins 7,500W Dual-Fuel Generator

    7500W
    Running
    74 dB
    Noise
    View details
  • Model RP6500 E
    Model RP6500 E

    Cat 6,500W Gas Generator

    6500W
    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 P9500dfCat RP6500 E
General
Product type
Generator
Generator
Fuel
Dual-Fuel
Gasoline
InverterNoNo
Parallel capableNoNo
RV readyNoNo
Running watts
Winner: Winner: 7500 W
6500 W
Starting watts
Winner: Winner: 9500 W
8125 W
Noise (lower limit)
Winner: Winner: 74 dB
0 dB
Weight
Winner: Winner: 194 lbs
202 lbs
Run time @50% load
11 h
Winner: Winner: 12 h
Run time @25% load
16 h
Not available
Fuel tank
6.6 gal
7.9 gal
Fuel gaugeYesYes
Approx. dimensions (L × W × H)
27.3 x 26.3 x 26.3
32.9 x 27.4 x 24.7
Electrical
Voltage (AC)
120/240
120/240
Voltage (DC)
Not available
Not available
GFCI outletsYesYes
Covered outletsYesYes
Automatic Voltage RegulationYesYes
THD
23 %
Not available
Engine
Engine
420 cc Ducar OHV 4-stroke
420 cc OHV 4-stroke
Alternator
Not available
Not available
Starting system
Recoil, Electric, Remote
Recoil, Electric
Warranty
Warranty
3 years
2 years
Power by fuel
GasolineNot availableNot available
Running watts
7500 W
6500 W
Starting watts
9500 W
8125 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
11 h
12 h
Run time @25% load
16 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
8 h
Not available
Other
Data center
Not available
Not available
Indicators
false
false
Compliance
EPA
CARB, EPA
Security
Not available
Not available
Spark arrestorYesYes
Neutral
true
true
UPC
690781007932
815683020067
Core / High-priority specs
Running Watts (Gasoline)
7500
6500
Running Watts (Propane)
6750
Not available
Starting Watts (Gasoline)
9500
8125
Starting Watts (Propane)
8550
Not available
Runtime @ 50% Load (Gasoline)
11
12
Runtime @ 25% Load (Gasoline)
16
Not available
Runtime @ 25% Load (Propane)
8
Not available
AC Outlet Types
2x Duplex 120V 20A (5-20R); 1x 120/240V 30A (L14-30R)
2x Duplex 120V 20A (5-20R); 1x 120/240V 30A (L14-30R); 1x 120V 30A (L5-30R)
Electrical & power
Frequency
60
60
Engine & construction
Engine Type
Ducar OHV 4-stroke
OHV 4-stroke
Engine Displacement
420
420
Engine Oil Type
SAE 10W-30
SAE 30 or 10W-30
Runtime & fuel system
Runtime @ 25% Load (Gasoline)
16
Not available
Runtime @ 50% Load (Gasoline)
11
12
Safety & compliance
Overload Protection System
Low oil and overload protection
Low oil and overload protection
Low Oil ProtectionYesYes
Carbon Monoxide MonitoringYesNo
Included equipment
Starting Components
Not available
Recoil, Electric
Included Accessories
Oil, funnel, tool kit, key fob, battery charger, propane hose, battery, and wheel kit
Oil, funnel, tool kit, battery, and wheel kit
Warranty & identification
Commercial Warranty
3
Not available
Part Number
A074Z438
502-3688
Additional specs
Summary
The Cummins Onan P9500df is a 7500-watt dual-fuel generator built for users who need sustained power across multiple scenarios. Running on either gasoline or propane, it delivers 9500 peak watts, enough to start large air conditioning units or power multiple job site tools simultaneously. The dual-fuel architecture means users can switch between fuel sources based on availability and storage constraints. Propane tanks store longer without degradation, while gasoline offers wider accessibility. This flexibility makes the unit valuable for both seasonal backup power and year-round work environments. The 194-pound weight and 27.3 x 26.3 x 26.3 inch footprint define this as a semi-portable unit. The included wheel kit enables movement across job sites or between storage locations, but this is not a grab-and-go machine. Users planning frequent relocation should factor in the logistical demands. The three-year commercial warranty covers manufacturing defects, giving buyers defined ownership support across the critical early-use period.
The Cat RP6500 E is a 6500-watt gasoline generator built for residential backup and light commercial work. Its 8125-watt peak capacity means it can start large tools and appliances that draw high inrush current, then sustain 6500 watts of continuous power for multiple devices simultaneously. A 7.9-gallon fuel tank delivers 12 hours of runtime at 50% load, which translates to roughly one full workday or overnight backup without refueling. The gasoline engine is straightforward to maintain and refuel anywhere, making this unit practical for job sites, outdoor events, and emergency home power.
  • Most Powerful
    Cummins Onan P9500df
    7500W running
  • Quietest
    Cummins Onan P9500df
    74 dB
  • Longest Runtime
    Cat RP6500 E
    12h at 50% load
Where to buy
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Cummins Onan P9500df
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Cat RP6500 E
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