Connect Honda EU1000i to a EU2000i WITHOUT Honda's cord

***Disclaimer-- As with my previous posts pertaining to things electrical, I'm an Electrical Engineer, DO NO try this at home. You will burn down your camper, kill your neighbor's dog, and smoke two very expensive generators if you do this wrong***


Since I just picked up a Honda EU2000i-Companion gen yesterday, and I already have a EU1000i. I thought I'd tackle two "Urban Legends".

1-- You can't hook dis-similar Honda's together
2-- You MUST use Honda's VERY expensive parallel cord to run two gen's together.

First -- research. I did a LOT of reading out there. There are tons of posts saying "Oh no, I HEARD you can't do that". I finally found credible posts that not only said, but showed you could.

Second -- Schematics. I found the schematics for each generator after a short Google search. Note the circle around the wiring for the outlets vs. the "Parallel Ports" - on both generators they are tied directly to the outlet.
WORSE YET-- The parallel ports on the 2000 BYPASS the breaker! Why did they do that???

So I made a simple 15a double-male cord using some heavy duty 12ga cord. Honda uses the "Parallel Kit" plugs for safety-- I just made a completely exposed double male cord. If you're drunk enough to grab hold of it while it's plugged into a running generator, you get bit. Honda's Parallel Kit - you can't get bit.

***There is no special signalling, sync'ing, or voodoo pixie dust on the parallel ports***. The inverters are auto-sensing for the 60hz sync at start up regardless whether you plug into the 110v plug or the parallel ports.

Schematics--
Note the 2000 parallel ports bypass the breaker--




1000 schematic--



My simple cord---



So, first, I of course VERY cautiously lit both off. No problem. I then plugged in my heat-gun. I used that first because it's a purely resistive load, and let's face it, very cheap if I smoked it.

Using a Kill-O-Watt meter, I checked it plugged into the wall first--
1580 watts.

Plugged it into the 1000's outlet, both gen's connected and running--
1550 watts. (a slight voltage difference between wall power and gen power). Both generators raised up off eco-idle and came up.

Removed the Kill-O-Watt meter from the heat gun, and plugged it into the Jumper Cable I made to see how much wattage the 2000 was putting out.
Fired up both Gen's, hit the heat gun again. The load was almost perfectly spread--The 2000 was sending 1040 watts through the circuit, meaning just over 50% of it's capacity. That also means by simple subtraction, the 1000 was putting 510 watts--also arguably close to 50% of it's rating.

Time to try it on the TC.

Left everything on--Converter, tv, Sat dish, etc. Hit the roof air, lit no problem, no struggle. Lit quick, both gen's revv'd up, then both came back down to just above the low-rpm eco speed.

The real test - hit the microwave with the roof air and everything else going. They both sped up, complained a lot, but never went into overload.


So why do all this, (besides to show we can) --
I can use the 1000 for charging batteries, leave the 2000 at home. It uses half the gas the 2000 does.
The 2000 - good for running everything, or just the roof air alone in ideal conditions (low altitude, no other power drain). Leave the 1000 at home.
Both gens - it's hot out, I'm camping in the mountains, and need the roof air.
But it's also nice to know I don't have to drag around a big, heavy $2200 EU3000i if I don't need it on any given trip. I can take one VERY small one, one slightly bigger one, or both.
***And the net cost of a 2000 + 1000 is several hundred less than a 3000.***

Worth noting--I also have a 2KW inverter w/6 batteries, so these gen's are not going to see a lot of use.