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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.

  • Firman H08051
  • Cat RP12000 E
  • Model H08051
    Model H08051

    Firman 8,000W Dual-Fuel Generator

    8000W
    Running
    74 dB
    Noise
    View details
  • Model RP12000 E
    Model RP12000 E

    Cat 12,000W Gas Generator

    12000W
    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
SpecificationFirman H08051Cat RP12000 E
General
Product type
Generator
Generator
Fuel
Dual-Fuel
Gasoline
InverterNoNo
Parallel capableNoNo
RV readyYesYes
Running watts
8000 W
Winner: Winner: 12000 W
Starting watts
10000 W
Winner: Winner: 15000 W
Noise (lower limit)
Winner: Winner: 74 dB
0 dB
Weight
Winner: Winner: 212 lbs
350 lbs
Run time @50% load
Winner: Winner: 12 h
11.7 h
Run time @25% load
Not available—
Not available—
Fuel tank
8 gal
13.2 gal
Fuel gaugeYesYes
Approx. dimensions (L × W × H)
30.2 x 27.5 x 26.3
35.7 x 32.7 x 35.8
Electrical
Voltage (AC)
120/240
120/240
Voltage (DC)
Not available—
12
GFCI outletsYesYes
Covered outletsYesYes
Automatic Voltage RegulationYesYes
THD
25 %
5 %
Engine
Engine
Firman Max-Pro Series OHV 4-stroke, cast iron sleeve
670 cc Rato OHV V-Twin
Alternator
Not available—
Not available—
Starting system
Recoil, Electric
Electric
Warranty
Warranty
3 years
2 years
Power by fuel
GasolineNot available—Not available—
Running watts
8000 W
12000 W
Starting watts
10000 W
15000 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
12 h
11.7 h
Run time @25% load
Not available—
Not available—
PropaneNot available—Not available—
Running watts
7250 W
Not available—
Starting watts
9050 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
5 h
Not available—
Run time @25% load
Not available—
Not available—
Other
Data center
Not available—
Not available—
Indicators
false
false
Compliance
CARB, EPA
CARB, EPA
Security
Not available—
Not available—
Spark arrestorYesYes
Neutral
Bonded to frame
true
UPC
840876180518
815683023891
Core / High-priority specs
Running Watts (Gasoline)
8000
12000
Running Watts (Propane)
7250
Not available—
Starting Watts (Gasoline)
10000
15000
Starting Watts (Propane)
9050
Not available—
Runtime @ 50% Load (Gasoline)
12
11.7
Runtime @ 50% Load (Propane)
5
Not available—
AC Outlet Types
1x Duplex 120V 20A (5-20R); 1x 120V 30A (L5-30R); 1x 120/240V 30A (L14-30R); 1x 120/240V 50A (14-50R)
2x Duplex 120V 20A (5-20R) GFCI; 2x 120V 30A (L5-30R); 1x 120/240V 30A (L14-30R); 1x 120/240V 50A (14-50R)
Electrical & power
Frequency
60
60
Engine & construction
Engine Type
OHV 4-stroke
670 cc Rato OHV V-Twin
Engine Displacement
439
670
Cylinder Sleeve
Cast iron
Not available—
Runtime & fuel system
Runtime @ 50% Load (Gasoline)
12
11.7
Runtime @ 50% Load (Propane)
5
Not available—
Safety & compliance
Overload Protection System
Low oil and overload protection
Low oil and overload protection
Low Oil ProtectionYesYes
Included equipment
Mobility Components
Wheel kit
Not available—
Starting Components
Recoil, Electric
Battery, Battery Charger, Wheel Kit
Fuel Connection Components
Propane hose
Not available—
Included Accessories
Oil, funnel, tool kit, propane hose, battery, and wheel kit
Oil, funnel, tool kit, battery charger, battery, and wheel kit
Warranty & identification
Commercial Warranty
3
Not available—
Part Number
Not available—
502-3700
Additional specs
Summary
The Firman H08051 is an 8,000-watt dual-fuel generator built to power job sites, homes during outages, and RV setups. Running on gasoline, it delivers 8,000 watts continuously and 10,000 watts at startup, enough to run a refrigerator, microwave, and multiple power tools at once. Switch to propane and the output drops to 7,250 watts running and 9,050 watts starting, a trade-off for fuel flexibility and longer shelf life. The 439cc cast-iron engine is engineered for durability in commercial and residential use. At 212 pounds, this is a stationary or semi-portable unit, not a grab-and-go machine.
The Cat RP12000 E is a 12,000-watt gasoline generator built for job sites, construction crews, and homeowners who need sustained power for multiple heavy tools or appliances simultaneously. The 15,000-watt peak output handles startup surges from air compressors, circular saws, and welders without stalling. At 350 pounds, this is a stationary or semi-portable unit. It ships with a wheel kit, battery charger, and full tool set, meaning users can operate it immediately without additional purchases.
  • Most Powerful
    Cat RP12000 E
    12000W running
  • Quietest
    Firman H08051
    74 dB
  • Longest Runtime
    Firman H08051
    12h at 50% load
Where to buy
Prices can change. We update these automatically.
Firman H08051
Store links
No links yet.
Cat RP12000 E
Store links
No links yet.
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