Honda Generator Polarity question

[John w]

Hi

I have searched the forum but cannot find specific reference to the Honda to thought to post here.

I have a 2011 Bavaria 36 cruiser & want to put a Honda generator on board for various uses, I borrowed a fellow boaters Honda eu 2000i generator & connected it to my shore power cable & ran it from the pontoon, when I went inside & turned on the 240v panel breakers it worked but showed a polarity red light powered up the boat for a few mins then shut the panel off. The generators owner has a Jeanneau 40 2003 vintage & he says it just plugged in & worked first time no issues without any warning lights!

Question did i connect it wrong?
I have read somewhere about earth & neutral cables causing a polarity issue but to be honest don't really understand it.
Can anyone aboard here can give me a idiots guide to what is happening & explain what I need to do to run the Honda on board Please.
Looking to purchase either a eu 2000i or the newer eu 22i.
Thanks
John

 

[RichardS]

That occasionally happens to me with both shore power and when using my Honda 2000.

I just unplug/shut down and start again. The second time the reverse polarity light stays out.

Richard

 

[Graham376]

My Honda has 2 pin Euro sockets so 50/50 chance of reverse polarity, everything works fine whichever way it's connected. My panel doesn't have polarity warning.

 

[davidpbo]

I am not surprised you got an error indication on the panel. The indicator lights may be wired for UK where normally the Neutral us connected to Earth somewhere in the supply chain. . Live is then usually at 240V or so with respect to N and nearly the same to Earth. I say usually because I got up at 06:15 last Friday and thought it was high time I got my eyes tested again, everything looked very dark. It was only when I went down, put our normally fast kettle on and not much happened and looked at the breadmaker which had not completed its cycle, that I realised something was up with the power. I had an installation in the house, we were getting 145Volts. Fortunately everything seems to have survived.

I doubt the generator is wired in this way. I was experimenting with my NUTool generator a few years ago and seem to remember the earth terminal in the outlet socket was not connected to the generator coils, live or neutral, I think it was connected to the chassis. That showed as a fault on a neon Martindale socket tester and that a working RCCD I plugged in to test did not operate

 

[Richard10002]

On mine I have a special short generator lead where the Neutral and Earth inside the plug that goes into the generator are connected. This sorts out the polarity lights in the boat.

I also understand that, without the connection in the plug, the RCDs in my consumer units wouldn't work.

 

[VicS]

Hi

I have searched the forum but cannot find specific reference to the Honda to thought to post here.


John

My Honda has 2 pin Euro sockets so 50/50 chance of reverse polarity, everything works fine whichever way it's connected. My panel doesn't have polarity warning.

I am not surprised you got an error indication on the panel. The indicator lights may be wired for UK where normally the Neutral us connected to Earth somewhere in the supply chain. . Live is then usually at 240V or so with respect to N and nearly the same to Earth. I say usually because I got up at 06:15 last Friday and thought it was high time I got my eyes tested again, everything looked very dark. It was only when I went down, put our normally fast kettle on and not much happened and looked at the breadmaker which had not completed its cycle, that I realised something was up with the power. I had an installation in the house, we were getting 145Volts. Fortunately everything seems to have survived.

I doubt the generator is wired in this way. I was experimenting with my NUTool generator a few years ago and seem to remember the earth terminal in the outlet socket was not connected to the generator coils, live or neutral, I think it was connected to the chassis. That showed as a fault on a neon Martindale socket tester and that a working RCCD I plugged in to test did not operate

You can find wiring diagrams for the Honda generators in the owners manuals. which you available online

You will see that the output is "non-polarised" ie the two output connections are identical. Neither is earthed to create a neutral.

The "earth" connections in the output sockets are only "earthed" to the generator chassis and the external earth terminal. and an RCD will not operate in the normal way, as David PBO says

Other makes of generators may be different

 

[Richard10002]

This is from the service book for my recently purchased Honda EU10i:



Sorry about the focus.

 

[davidpbo]

Obviously that works for your generator. I would be wary of using something like that without knowing how the generator is wired unless it says it is permissable in the manual.

On mine I have a special short generator lead where the Neutral and Earth inside the plug that goes into the generator are connected. This sorts out the polarity lights in the boat.

I also understand that, without the connection in the plug, the RCDs in my consumer units wouldn't work.

 

[PaulRainbow]

Obviously that works for your generator. I would be wary of using something like that without knowing how the generator is wired unless it says it is permissable in the manual.

It is very important to note, that whilst this works with the Honda generator, it can cause irrepairable damage to other generators.

It is equally important to note, if a generator is going to be connected to onboard systems and it cannot have the neutral and earth bonded, it has no place on the boat. No not connect these generators to onboard systems.

 

[Richard10002]

Obviously that works for your generator. I would be wary of using something like that without knowing how the generator is wired unless it says it is permissable in the manual.

That's why I posted the page including Hondas advice.

 

[Richard10002]

It is very important to note, that whilst this works with the Honda generator, it can cause irrepairable damage to other generators.

It is equally important to note, if a generator is going to be connected to onboard systems and it cannot have the neutral and earth bonded, it has no place on the boat. No not connect these generators to onboard systems.

The OP asked about a Honda generator, I responded with information related to my use of a Honda, and I did post a page containing Hondas advice.

For clarity, are you saying that a generator that "cannot have the neutral and earth bonded" should "not" be connected to the shore power input in order to run the battery charger and other on board 240V stuff?"

 

[VicS]

It is very important to note, that whilst this works with the Honda generator, it can cause irrepairable damage to other generators.

It is equally important to note, if a generator is going to be connected to onboard systems and it cannot have the neutral and earth bonded, it has no place on the boat. No not connect these generators to onboard systems.

The OP asked about a Honda generator, I responded with information related to my use of a Honda, and I did post a page containing Hondas advice.

For clarity, are you saying that a generator that "cannot have the neutral and earth bonded" should "not" be connected to the shore power input in order to run the battery charger and other on board 240V stuff?"

I imagine PR meant to say, "Do not connect these generators to on board systems."

I think the logic is that if one conductor cannot be earthed to form a neutral as shown in your service manual an RCD will not work and that a generator which will not allow an RCD to work should not be connected to on board systems.

I therefore understand that a generator with an "centre tap " earthed output and cannot used in the way the Honda manual suggests will, as a result, be unsuitable for connection to a conventional onboard shorepower system.

 

[PaulRainbow]

The OP asked about a Honda generator, I responded with information related to my use of a Honda, and I did post a page containing Hondas advice.

I realise you were talking about the Honda generator Richard. I was adding a note for other readers, to make clear that not all generators can be connected this way.

For clarity, are you saying that a generator that "cannot have the neutral and earth bonded" should "not" be connected to the shore power input in order to run the battery charger and other on board 240V stuff?"

Yes that's exactly what i'm saying.

 

[PaulRainbow]

I imagine PR meant to say, "Do not connect these generators to on board systems."

I think the logic is that if one conductor cannot be earthed to form a neutral as shown in your service manual an RCD will not work and that a generator which will not allow an RCD to work should not be connected to on board systems.

I therefore understand that a generator with an "centre tap " earthed output and cannot used in the way the Honda manual suggests will, as a result, be unsuitable for connection to a conventional onboard shorepower system.

That's all spot on Vic

 

[Travelling Westerly]

Reading this has me conerned now as I think I may be using my EU20i outside of Pauls advice!

I run my Honda when at anchor and have not bothered to use the earth connection on the front panel. My boats 240v earth is not earthed to the DC ground side either (which Ive read is fine).

Should I run a ground from the Honda front panel and if so to what?

 

[FulmarJeddo]

We also have a Swift Caravan, I don't have the handbook to hand, but it definitely says something about the reverse polarity may light when run on a generator. It doesn't give a reason, but says it is acceptable. It could be worth searching caravan forums for more information.

 

[rogerthebodger]

We also have a Swift Caravan, I don't have the handbook to hand, but it definitely says something about the reverse polarity may light when run on a generator. It doesn't give a reason, but says it is acceptable. It could be worth searching caravan forums for more information.

The real point about a generator or inverter that is not center tapped and also does not have its neutral/earth linked is that any RCD in circuit will not trip.

Some people think this is dangerous. It is not as safe as with an operating RCD but is the same as electrical installations in the UK when I was growing up.

My non inverter Honda generator did not have an neutral/earth connection but worked OK was the same as most balanced systems.

The point that VicS made and PR agreed with is to determine if your generator or inverter is a center tapped device. If it is not connect neutral to earth at the generator or inverter.

If your device is center tapped DO NOT as there will be a big bang.

The issue is how does a non technical person determine of your device is center tapped or not.

 

[Graham376]

Reading this has me conerned now as I think I may be using my EU20i outside of Pauls advice!
I run my Honda when at anchor and have not bothered to use the earth connection on the front panel. My boats 240v earth is not earthed to the DC ground side either (which Ive read is fine).
Should I run a ground from the Honda front panel and if so to what?

I have been plugging my Honda in to the shore power socket for years without any problems. When I get back, I'll check if the comments about the rcd are correct but will no doubt continue to use it anyway. Over the years, pre rcd and double insulated appliances, I've had countless mains belts so may be due for another