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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.

  • Cummins Onan P4500i
  • Cat INV2000
  • Model Onan P4500i
    Model Onan P4500i

    Cummins 3,700W Gas Generator

    3700W
    Running
    52 dB
    Noise
    View details
  • Model INV2000
    Model INV2000

    Cat 1,800W Gas Generator

    1800W
    Running
    52 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 P4500iCat INV2000
General
Product type
Generator
Generator
Fuel
Gasoline
Gasoline
InverterYesYes
Parallel capableYesNo
RV readyYesNo
Running watts
Winner: Winner: 3700 W
1800 W
Starting watts
Winner: Winner: 4500 W
2250 W
Noise (lower limit)
Winner: Winner: 52 dB
Winner: Winner: 52 dB
Weight
98 lbs
Winner: Winner: 48.8 lbs
Run time @50% load
Winner: Winner: 15 h
6 h
Run time @25% load
18 h
10 h
Fuel tank
3.4 gal
1 gal
Fuel gaugeYesYes
Approx. dimensions (L × W × H)
24.5 x 18.3 x 20.5
19.6 x 12.5 x 18.1
Electrical
Voltage (AC)
120
120V 60 Hz
Voltage (DC)
5
12
GFCI outletsNoYes
Covered outletsYesYes
Automatic Voltage RegulationYesYes
THD
3 %
<3% %
Engine
Engine
224 cc Ducar OHV 4-stroke
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
3700 W
1800 W
Starting watts
4500 W
2250 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
15 h
6 h
Run time @25% load
18 h
10 h
Other
Data center
Not available
Not available
Indicators
true
true
Compliance
CARB, EPA
CARB, EPA
Security
Not available
Not available
Spark arrestorYesYes
Neutral
Floating
true
UPC
690781007925
815683024881
Core / High-priority specs
Running Watts (Gasoline)
3700
1800
Starting Watts (Gasoline)
4500
2250
Runtime @ 50% Load (Gasoline)
15
6
Runtime @ 25% Load (Gasoline)
18
10
AC Outlet Types
1x Duplex 120V 20A (5-20R); 1x 120V 30A (TT-30R)
1x Duplex 120V 20A (5-20R) GFCI
Electrical & power
Frequency
60
60
Engine & construction
Engine Type
Ducar OHV 4-stroke
OHV 4-stroke
Engine Displacement
224
79.7
Engine Oil Type
10W30
SAE 30 or 10W-30
Runtime & fuel system
Runtime @ 25% Load (Gasoline)
18
10
Runtime @ 50% Load (Gasoline)
15
6
Safety & compliance
Overload Protection System
Low oil and overload protection
Low oil and overload protection
Low Oil ProtectionYesYes
Included equipment
Included Accessories
Oil, funnel, tool kit, key fob, battery charger, and battery
Tool kit
Warranty & identification
Commercial Warranty
3
2
Part Number
A058U955
Not available
Additional specs
Summary
The Cummins Onan P4500i is a 3700-watt inverter generator built for users who need reliable power without the noise penalty. Its 4500-watt peak capacity handles startup surges for air conditioners, power tools, and RV air conditioning units. The gasoline engine runs clean enough for sensitive electronics like laptops and phones, thanks to a 3 percent THD rating that protects against voltage spikes. This unit bridges the gap between portable camping generators and stationary backup power, making it useful for RV owners, homeowners facing extended outages, and contractors working near occupied spaces.
The Cat INV2000 is an 1800-watt inverter generator built for users who need portable, clean power without the noise. At 48.8 pounds and measuring 19.6 x 12.5 x 18.1 inches, this unit bridges the gap between lightweight portability and genuine load capacity. It runs on standard gasoline and produces less than 3% THD, meaning laptops, phones, and sensitive electronics stay safe from voltage spikes. The recoil start fires up quickly, and the 52 dBA noise level keeps it quiet enough for residential areas and campgrounds. With 10 hours of runtime at 25% load and 6 hours at 50% load, users can power essential devices through a full day or night without refueling. The 1-gallon fuel tank and automatic low-oil shutdown mean less maintenance worry. This is a grab-and-go generator for camping, tailgating, emergency backup, and light outdoor work where portability matters as much as power.
  • Most Powerful
    Cummins Onan P4500i
    3700W running
  • Quietest
    Cummins Onan P4500i
    52 dB
  • Longest Runtime
    Cummins Onan P4500i
    15h at 50% load
Where to buy
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Cummins Onan P4500i
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Cat INV2000
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