What you need to split your 240V outlet…
The best way to get the full power out of your generator’s 240V outlet is by using a Generator Power Splitter. A good example of this is our 30Amp to (2) 15/20Amp Power Splitter.
Many generators give you a single 240V outlet, and two or three 120V standard household outlets. Each are wired differently in the generator.
240V outlets use 2 live wires to carry current, and are wired to both windings on most generators.
The 120V outlets will only use 1 live wire, and connect it to only one winding, limiting your power usage.
Why you need a special cord…
Say you have a 7500 watt generator. This means it has two separate 2500 Watt, windings. It has the typical household outlets, and a 240V outlet. (example right)
The home outlets are typically wired to one winding. However, the 240V outlet is wired to both windings on the generator.
The left outlets can only deliver 2500 watts because it is wired to one winding. The right outlet is wired to both.
Splitting this outlet into two regular outlets will yield 2500W to both of them. You are now taking full power from both windings in your generator and using the unit to its full capacity.
What can happen if you don’t use the splitter?
If you only plug into the 120V outlets, you only have access to 2500 watts. Loading this end with too many items won’t stall the generator, but it might trip the breaker on the generator. Worst case scenario is the breaker fails, causing the winding to prematurely wear / fail.
The moral of the story…
Using this splitter will save you the headache of tripping breakers, and not getting the power you need from your generator.
If two outlets are not enough, you can still plug an ordinary triple tap or distribution cord into the splitter. Rest easy knowing now you are spreading that load evenly over both windings in your generator.
Always make sure to check your generator’s owner’s manual to see if all the 120V outlets are attached to only one winding. Some more expensive units may have 120V outlets on both windings, and in that case you will not need to worry about this solution.
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I have a Generac GP3250 that has two 110v outlets and an L14 240v twist lock outlet. Voltage at the 110v outlet is 120 but voltage of each leg on the 240v outlet is 125vdc. Why the difference? Also, I have a rectifier that will run on pwr from the 110v outlet but if I try to run it off of one leg of the 240v oulet, it blows the fuses on the ac side.Why?
Hi Thomas,
I would recommend you contact the manufacturer for those questions.
As far as the voltage is concerned though, companies tend to use numbers such as 110, 120, or 125 for the voltage label. The max output of a 3 prong US household outlet is 1875 watts (15 amps X 125 volts). The lower denominations found tend to be a safe number that they are estimating for the actual output.
More often then not the plug is split so each plug is a different phase of the winding.
Good explanation for advertising purposes. However, if you consult your generator’s wiring diagram, you may find (like I did) that each of the two 115V outlets is wired to different windings in the generator. My WheelHouse 5550 manual tells me that I’ll get 2400 Watts from each of the 115V outlets or 2750 Watts from each hot leg of the 240V outlet (L14-30R). There is a difference there but probably due to the outlets themselves since the same wires go to the 240V outlet that go to each of the 115V outlets. I would guess that if you have more than one 115V outlet, your genset manufacturer is supplying power to each from separate windings.
I’m using my generator to charge my batteries on solar system. trouble is my generator is gfi protected and it trips .. So my 240 outlet is not gfi protected.. I”ve been told it’s going to be hard on the windings if i split 240 into 120v..if i use your splitter but only use one plug would it damage generator??
I have a Magnum MLT3060 Generator/light tower with a 6KW Marathon brushless generator on the unit, it has (1) 120-volt outlet and (1) 240-volt outlet, I would like to add (1) 50 amp
outlet to use when the light tower is not in use to power an external portable power distribution panel for an entertainment stage (Light and sound) any help would be very appreciated!