Honda generator output question

[lenz]

I see several posts from people with the Honda 2000 generator. I have the EU2000i model which means it has an inverter in it which allows the engine to idle down as the current demand goes down. On this model the outlets produce 60 volts on each side of the outlet. So if you measure across the 2 "hot" wires you get 120 volts, but if you measure from either side of the outlet to ground you get 60 volts. When plugged into the shore power inlet the voltage on the breaker panel only shows 60 volts (which is a bit concerning). Everything seems to be working ok, and Honda technical support tells me this is the way the inverter models work. Anyone else have a similar experience? Any electricians out there that can tell me if it's ok to operate this way?

 

[Wee Venture]

I am not an electrician. I have been waiting for someone else to weigh in but I’ll take a shot. The Honda 2000, like similar portable generators, has a floating neutral (really no neutral, but one side is connected to the neutral on your boat so we then refer to it as the “neutral” wire). It is floating because it is not connected to ground at the source. The neutral should ideally be bonded to the ground at the source *and nowhere else*. In a home, it is at the service entrance only. On a boat, it is at the shore power source on shore and not on the boat.

The one exception to that is when the inverter is the power source. Many inverters on older boats are wired incorrectly and create ground faults when the boat is connected to shore power. The owners often only find this out when they connect to a marina power pedestal that has been updated to the newest standards.

This brings us to the Honda 2000. When the Honda is plugged into the shore power receptacle on your boat it becomes the power source. Therefore it is ok and probably a good idea to ground the neutral at the generator. You can buy a special plug for this purpose that already has the neutral and ground connected internally. Then you simply plug it into the unused receptacle on your generator. (Never leave this plug in place, though, if you ever connect the generator’s output to your house wiring. The possibility that people may use their generators in that way is why the neutral and ground were left unbonded in the first place.)

If you bond the neutral to ground at the generator, it becomes functionally the same as when your inverter supplies power, and I think your meter will read correctly at 120VAC. But then there is the question of why it reads 60VAC now. Not sure, but I’m going to hazard a guess that your meter is connected between the hot wire and ground rather than hot and neutral. The ground on your boat will be connected to the metal frame of the generator through your “shore power” cord’s green ground wire. You are probably measuring stray capacitive micro-currents from within the generator since the neutral has been left ungrounded.

Anyone can feel free to chime in here but that’s my take.

Here is the link to the plug:
https://www.amazon.com/Southwire-Compan ... B07F4R7BDL

John

 

[Osprey]

Wee Venture’s comments are consistent with my experience using both an EU 1000i and an 2000i Honda generator. One can buy the special plug or on the other hand it is a simple matter to make one using a standard 3 pin plug and a jumper wire. Connect the jumper wire between the ground and neutral pins. Just make sure you recognize the difference between the neutral and hot pins.

 

[lenz]

Thank you for the detailed explanation. It makes sense. I'll give the plug a try.

 

[knotflying]

Without the jumper you will get a reverse polarity.
As far as the technical explanation goes, great job. Just to add a bit about the 60V on each leg. Electric runs in a cycle. Think about appliances that you have like a dryer. They are 240V. So what happens is it is actually grabbing 120V from two different legs in your panel and as they cycle opposite from one another they are actually powering each leg at 120V for a total of 240V. So I would assume the same is happening with each leg of the generator, each at 60V for a total of 120V.