- Wattage (Gas): 3,500 W / 3,000 W
- THD: < 3%
- Noise Level: Unspecified
- Fuel Type: Gasoline
- RV Ready: No
- Run Time@ 25% load: 11 h
- Run Time@ 50% load: 8 h
- Weight: 74.3 lbs
Table Of Contents
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The gasoline-powered Generac OHV 4-stroke 212 cc engine is the heart of the Generac GP3500iO. It has a 120V output and a running power of 3,000W and a peak power of 3,500W. It can also work in parallel (GP3500iO Parallel Kit not included), which means that its power can be doubled if it is connected to a second compatible unit. It uses a simple, traditional pull-start mechanism to get going. It has Generac’s PowerDialTM, which is an easy-to-use dial with three settings for how the generator works. With a full tank, the GP3500iO can run for up to 11 hours (using about 0.22 GPH of fuel), since it can hold 2.37 gallons of fuel. The GP3500iO makes a clean sine wave. With a Total Harmonic Distortion (THD) of less than 3%, you can safely plug your sensitive electronics into the AC outlets.
On the control panel, there are 3 AC outlets: a duplex 120V 20A (5-20R) outlet and a 120V 30A (L5-30R) outlet.It also has 2 DC outlets: two 5V USB ports that make it easy to charge devices like cell phones or tablets.Even though this Generac generator isn’t quite RV Ready, an L5-30P to TT-30R adapter makes it easy to connect it to an RV.
The GP3500iO’s control panel has a digital data center that tells you how many hours it has been running for so you can keep an eye on its status and activity.In addition to this information, some lights let you know right away if the generator is ready, if it is overloaded, or if it doesn’t have enough oil.For safety, the generator has an automatic low oil shut-off and an overload protection (circuit breaker), so you can use it without worrying.The Generac GP3500iO comes with standard paperwork and an owner’s manual that will help you get the device up and running quickly.It also comes with a tool kit, oil, and a funnel.
The Generac GP3500iO is made with a typical open frame that measures L19.3 x W16.9 x H16.4 in, This frame gives the generator support and stability and lets you raise it above ground level.The device was made to work well in harsh conditions and in the great outdoors.Because it weighs 74.3 lbs, you can take the GP3500iO anywhere.The generator is also easier to pick up and move around because its frame is open.
The following charts show how some of the most important features of the Generac-7128-GP3500iO compare to other generators with the same power output.
**Fuel efficiency is give in relative percentage, 0 being the lowest and 1 being the highest value. Please see below specification table for actual value.
|Yes, cable not included
|212 cc Generac OHV 4-stroke
|AC: 120V 60 Hz, DC: 5V
|Running amps (@120/240V)
|Peak amps (@120/240V)
|Run time @50% load
|Run time @25% load
|Automatic Voltage Regulator
|1x Duplex 120V 20A (5-20R); 1x 120V 30A (L5-30R)
|2x 5V USB port
|Lifetime run hours
|Low oil, overload and output ready
|Approx. dimen. (L x W x H)
|19.3 x 16.9 x 16.4 in
|Noise (lower limit)
|Low oil and overload protection
|Oil, funnel, and tool kit
- We compared more than 500 portable generators at 50% load. We found that there is “skewed right” distribution for the difference between 50% load and 25% load and the median comes at 1.43. With this number we converter all the 25% load runtime to 50% load. Same with the propane efficiency, where median is 1.38.
- For some generators where propane runtime was not given, we used NIST 1994 GGE (Gasoline Gallon Equivalent) formula: 5.66 lbs. of propane = 1 gal of gasoline. All propane runtime is for 20 lbs. propane tank (4.7 gallons).
- Unlike many other sites, we actually tried to find out information about each of the above requirements. However, we are human and are therefore capable of the odd oversight or mistake. Please let us know if you spot any missing or erroneous values so that we can fix them.
About the Manufacturer
Founded in 1959, Generac Power Systems is an American manufacturer of power tools and generators.Generac’s primary business is, as its name implies, the manufacture of power generators as well as other electrically related products like switches, paralleling systems, and tiny engines.The corporation has multiple US-based production facilities, thus its goods are produced there.The company, however, doesn’t disclose where the components they use were made.
The warranty for the Generac GP3500iO lasts for up to 3 years.This warranty may not cover all parts of the generator or may only cover certain parts.Generac’s warranty policies can tell you more about how long generators are covered by warranty.You can also call their customer service line at 1-888-GENERAC (888-436-3722).