Hooking Up Two Inverter Generators, Its Done, Just Wires?

Con #2: If there is an outage, you might not be able to start the other generator.3. The mayberrys/wise sales method: This is the method that I used. Basically, what you do is buy a https://www.amazon.com/dp/B005HYDJKM/?tag=pfamazon01-20 from a mayberrys or wise sales person and have them make the connections for you.Pro: SafeCon: You might have to pay for this service.4. The https://www.amazon.com/dp/B006YBB5EY/?tag=pfamazon01-20 method: This is the method that I usedf
  • #1
Hello, http://www.powerequipmentdirect.com/Reliance-Controls-GPK30RV/p1893.html Reliance Controls Sidewinder™ Parallel Power RV Cables is an example of this. That one is universal. Honda makes same thing for their invertor generators, plug two 2,000 watt together to get 4,000 watts.

Intriguing. Looking at picture at that site, it looks like $99 for wiring two to one. No box. Just a plug. I have posted on dilemma of 800 watt inverter (earthquake brand) that is super light and quiet but trips on 780 watt drill on startup. Am now planning on getting second one (inv/gen) and did get smaller drill. But if can hook two of these cheap 21 pound quiet gens together, wow would have 1600 watts that would cover all our power tools.

What do the experts think here? Is that link http://www.powerequipmentdirect.com/Reliance-Controls-GPK30RV/p1893.html just wires we can do ourselves, or do those have some sine wave matching circuit in them?
  • #2
More info this guy has hooked up a 1,000 a 1,000 and a 2,000 and says works great and you can turn one off after you get past startup amps Its a long video so a skipped through it but appears to be just wires, nothing more.

https://www.amazon.com/dp/B00K2YDNWG/?tag=pfamazon01-20 is a cheaper kit. Maybe has just wires maybe there is a circuit?
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  • #3
Found this here: http://www.outbackers.com/forums/index.php?showtopic=10288

Here is a cut and paste from the above post. j1mfrog summed it all up. To save your search time.

He writes,
Sorry the pictures below are so small, I don't know how to make them show up big. They are in my Gallery where you can see them larger.

Well after being told that the two outputs were simply wired in parallel, I finally figured that I needed to do a little research on my own. You see I’ve read a lot about the Honda
https://www.amazon.com/dp/B00KPQZJIW/?tag=pfamazon01-20 and paralleling and inverter technology on this forum and maybe some others as well whistling.gif but I never seemed to get the whole picture. Some of it was just wrong; I had read previously that the two outputs were different. Looking back; I don’t know why I would have taken that at face value, it doesn’t make sense. unsure.gif

So I went to the owner’s manual and got the whole picture, and here it is.

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This is the wiring diagram for a Honda EU200i taken from the owner’s manual, which I downloaded from the Honda site. From this wiring diagram, a person with a working knowledge of electricity can make some important conclusions.

1. The Banana jack output and the standard three-prong outlet are wired in parallel, just as Kevin stated above. Thanks for that simple eye-opening piece of information Kevin.
2. The Banana jack output is not protected by a circuit breaker. This is important and leads me to a discussion of the safety of the various methods of paralleling these units.

First I would like to dispel a myth, which I myself am guilty of spreading shy . The myth is that you have to parallel through the banana jack outlets. Some have said that Honda has an auto-synchronization circuit that is only connected through the banana jacks. This is untrue. It is true that the inverter technology utilized by Honda allows this auto-synchronization, but the wiring diagram clearly shows that the two outputs are electrically the same point, so you can parallel with either output.

Now let’s talk safety. ph34r.gif I see four basic methods to parallel. I’ll list them then talk pros and cons of each. Please feel free to correct me where I’m wrong or clarify where I’m vague.

1. Honda factory made parallel kit.
2. Three-prong method.
https://www.amazon.com/dp/B00HUY2RG4/?tag=pfamazon01-20 method
4. Mayberrys/Wise sales method (Honda authorized parallel kit)

1. Honda Parallel Cables (See parts catalog below): The
https://www.amazon.com/dp/B00QKSGKXC/?tag=pfamazon01-20 is a bit of a mystery to me, I don’t see the advantage, and maybe someone can clear this up for me. It parallels the two generators but the paralleled output still has to come through 16.7 amp receptacles. What do you gain? You don’t have a built in 30 amp breaker on the generator. This method is safe but you don’t really gain anything from your effort. This statement is copied from the https://www.amazon.com/dp/B002E9VI4C/?tag=pfamazon01-20: “Parallel Cables: (EU1/EU2 only) links 2 EU1000is or 2 EU2000is – Includes ground wire connection. Note: Output is limited by the capacity of the receptacles.”

Pro: Safe
Con: waste of time and effort.

2. Three prong method: This method is safe to a degree. Basically what you would do is take three feet or so of heavy-duty
https://www.amazon.com/dp/B006YBB5EY/?tag=pfamazon01-20 with male ends on them, run them to a box where you would splice them and connect them to a thirty https://www.amazon.com/dp/B005HYDJKM/?tag=pfamazon01-20.

Pro: Breaker protected
Con #1: If one three-prong lead becomes unplugged with the other generator running, you’ve got a hot plug lying on the ground. It is circuit breaker protected, but still hot.

Con#2: On a heavy draw, if one circuit blows, the other would probably follow immediately. This is not that big of a deal, but I’d rather run my
through one circuit than two. Personal preference.

3. The
https://www.amazon.com/dp/B00HUY2RG4/?tag=pfamazon01-20 Method: Parallels two https://www.amazon.com/dp/B00KPQZJIW/?tag=pfamazon01-20 though the banana jack outputs directly to a thirty https://www.amazon.com/dp/B005HYDJKM/?tag=pfamazon01-20.

Pro: Cheap

Con #1: If one of the banana jacks comes out, the other is hot as described above for the three-prong circuits. The risk is higher in one aspect; no
https://www.amazon.com/dp/B00P3FJT1S/?tag=pfamazon01-20, but lower in another; the banana jacks used have a built in jacket. (Actually I’m not sure Big Sky uses these, but they should.)

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Con #2: The
https://www.amazon.com/dp/B00HUY2RG4/?tag=pfamazon01-20 Parallel kit does not have a built in circuit breaker. That would not be a big deal if what they told Jared was true, but it is not.

“The answer from big sky: We do not add a breaker because the units have internal breakers that work well. Can I build one? Sure, we don't really do anything special, just ensure that you use the parallel plugs not the standard 120 outlets because you will not draw a full 30 amps, those plugs are limited to 16.7 amps even when synchronized.
That is why their kit is $90 instead of 200+ (when you buy with the generator).”

Look at the wiring diagram; you won’t see a circuit breaker on the banana jack output. So what? Well, what that means it that the first protection afforded is at the main circuit breaker on the distribution panel in your camper. If you have a fault between the
https://www.amazon.com/dp/B00KPQZJIW/?tag=pfamazon01-20 and your camper panel, there is an increased risk of fire, electrical shock, and burning up your $1000 generators. I was previously leaning towards this method. Now I believe that it is too unsafe. I will not risk it.

4. The Mayberrys/Wise Sales method, AKA the Honda authorized method: (see parts catalog below). This method takes the output from the banana jacks, parallels the two, runs them through a thirty-amp circuit breaker, then to a thirty amp female receptacle.

Pro: Negates con #2 of the
https://www.amazon.com/dp/B00HUY2RG4/?tag=pfamazon01-20 method with the use of a circuit breaker. Puts the protection at the generators (the source). Pro #2 is that this is a Honda factory authorized part.

Con #1: Same as Big Sky Con #1. If one of the banana jacks comes out, the other is hot as described above for the three-prong circuits. The risk is higher in one aspect; no
https://www.amazon.com/dp/B00P3FJT1S/?tag=pfamazon01-20 (the circuit breaker is after the splice), but lower in another; the banana jacks used have a built in jacket.

Con #2: Expensive. Probably overpriced in my book. I believe they can get away with this because this part is actually listed in the
https://www.amazon.com/dp/B002E9VI4C/?tag=pfamazon01-20 even though Honda does not manufacture it. This setup could probably be built by many of us. But if you buy the one endorsed by Honda, that’s got to give you a warm fuzzy.

I’ve said a lot. I really don’t believe too many people are still reading this except for those who are about to make a purchase or who have done this research already.

Feel free to correct me where I’m wrong.


that post and others talk about Big Sky as if it is a product, which I can not find. Maybe it is a joke, as in means DIY It does seem to be just wiring them together and they self sync. Does that sound plausible to the experts here?
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