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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
  • Aceup Energy AI4000DS
  • Model Onan P4500i
    Model Onan P4500i

    Cummins 3,700W Gas Generator

    3700W
    Running
    52 dB
    Noise
    View details
  • Model AI4000DS
    Model AI4000DS

    Aceup Energy 3,200W Generator

    3200W
    Running
    55 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 P4500iAceup Energy AI4000DS
General
Product type
Generator
Not available—
Fuel
Gasoline
Not available—
InverterYesNo
Parallel capableYesYes
RV readyYesNo
Running watts
Winner: Winner: 3700 W
3200 W
Starting watts
Winner: Winner: 4500 W
4000 W
Noise (lower limit)
Winner: Winner: 52 dB
55 dB
Weight
Winner: Winner: 98 lbs
Not available—
Run time @50% load
Winner: Winner: 15 h
8 h
Run time @25% load
18 h
Not available—
Fuel tank
3.4 gal
1.32 gal
Fuel gaugeYesNo
Approx. dimensions (L × W × H)
24.5 x 18.3 x 20.5
Not available—
Electrical
Voltage (AC)
120
120V
Voltage (DC)
5
12V
GFCI outletsNoNo
Covered outletsYesNo
Automatic Voltage RegulationYesNo
THD
3 %
Not available—
Engine
Engine
224 cc Ducar OHV 4-stroke
149cc 4-stroke OHV engine
Alternator
Not available—
Not available—
Starting system
Recoil; Electric; Remote
Not available—
Warranty
Warranty
3 years
2 years
Power by fuel
GasolineNot available—Not available—
Running watts
3700 W
3200 W
Starting watts
4500 W
4000 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
Not available—
Run time @25% load
18 h
Not available—
Other
Data center
Not available—
Not available—
Indicators
true
true
Compliance
CARB, EPA
EPA compliant
Security
Not available—
Not available—
Spark arrestorYesNo
Neutral
Floating
Not available—
UPC
690781007925
Not available—
Core / High-priority specs
Running Watts (Gasoline)
3700
3200
Starting Watts (Gasoline)
4500
4000
Runtime @ 50% Load (Gasoline)
15
Not available—
Runtime @ 25% Load (Gasoline)
18
Not available—
AC Outlet Types
1x Duplex 120V 20A (5-20R); 1x 120V 30A (TT-30R)
One 20A outlet, one L5-30R Twist-Lock receptacle
Electrical & power
Frequency
60
60
Engine & construction
Engine Type
Ducar OHV 4-stroke
4-stroke OHV
Engine Displacement
224
149
Engine Oil Type
10W30
Not available—
Runtime & fuel system
Runtime @ 25% Load (Gasoline)
18
Not available—
Runtime @ 50% Load (Gasoline)
15
Not available—
Controls & display
Display Type
Not available—
Intelligent gauge
Idle Control System
Not available—
Economic mode
Safety & compliance
Overload Protection System
Low oil and overload protection
Not available—
Low Oil ProtectionYesNo
Carbon Monoxide MonitoringNoNo
Included equipment
Included Accessories
Oil, funnel, tool kit, key fob, battery charger, and battery
Oil funnel * 2; A bottle of Oil; Spark plug wrench
Warranty & identification
Residential Warranty
Not available—
2
Commercial Warranty
3
Not available—
Part Number
A058U955
SKU ‎AI4000s
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 Aceup Energy AI4000DS is a 3200 watt rated gasoline generator with a peak output of 4000 watts, featuring a 149cc 4-stroke OHV engine and EPA compliance.
  • 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
Prices can change. We update these automatically.
Cummins Onan P4500i
Store links
No links yet.
Aceup Energy AI4000DS
Store links
No links yet.
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