Reverse Polarity

[ahill]

When I run my Honda 2000 I generator I get a (faint) reverse polarity light on my AC panel. On Regular shorepower it does not glow. I was told this is due to the generator being an inverter, not a traditional AC power supply.
Any similar experience?

 

[Tuna Man]

I am curious also. I plan on doing the same thing this summer on overnight trips.

Have you checked the polarity of your cords? In other words, is your hot leg (normally the small slot on a regular 120 volt outlet) coming from the generator going to the hot leg on your shore power cord inlet mounted to the boat? The same idea for the nuetral leg on both ends of your cord(s).

I have not tried it yet on my boat so I cannot answer. Hopefully someone else can.

 

[BobP]

Is there a third wire coming out of the honda?

If so, is it supposed to be connected to the ship's ground ?

 

[Grog]

Is there a third wire coming out of the honda?

If so, is it supposed to be connected to the ship's ground ?

Every modern portable generator I've seen has gounded outlets. Unless the machine is bonded to ground (rubber wheels and feet don't do it), the ground from the extension cord is useless and neutral isn't neutral.

I couldn't find boat wiring in the NEC code book but the ground lug is probably tied to an underwater fitting and the neutral is tied to the ground bar. Definitely use GFCI outlets and you can't plug a GFCI into a GFCI.

 

[BobP]

I say this since a reverse polarity sensor needs a reference to know what is correct and what is incorrect.

120V Neutral white is always connected to the ground green at the source of power (supposed to be), the Hot black leg - never.

So if the honda is floating the neutral, that may cause the flickering. If I had the owners manual, and it was worth the paper it was printed on, I would have the question resolved.

To verify proper wiring, the member can get one of the devices with the different color LEDs that plug in an outlet and indicate via color code if the connections are correct and if not, what is wrong. I have one from Sears, bought it 20 yrs ago for about 15 bucks. This is a good device to use to see if shore power earth grounding circuits are of integrity, too.

 

[Grog]

What is Honda going to bond the neutral to? It doesn't ship with a grounding rod.

 

[BobP]

The Honda neutral to the Ships grounding system, both DC and AC, there is nothing else to connect to.

My motors and zincs are all in saltwater always, conneced to battery negs, Atlantic Ocean makes for best earth ground there is !

If the Honda is using an engine driven DC generator to supply the DC to AC inverter, question is - is there a third wire at the Honda receptacle, and what are you supposed to do with it. My inverter receptable has GFCI and third wire. I grounded inverter case to ship's grounds, DC and AC.

 

[BobP]

And you can feed a GFCI from another GFCI , etc, no harm will come of it, not needed though, and may get false trips. GFCIs are not interested in ground, earth, 3rd green wire, or otherwise, they don't need it nor care about it to get the job done they are intended for. Two wires needed only.

 

[Grog]

If you feed a GFCI through a GFCI the first one will trip. No harm will come of it but you will not get any power out of the second GFCI, try it.

GFCI's don't give a ___ about the ground and wherever you have a questionable ground it's recommended to use GFCI's. Any current that doesn't flow back through the neutral will trip it and if there isn't a ground to help keep you from being a conductor they come in handy.

On an older boat I'd check to be sure the ground is grounded. Besides you may not know who installed the shore power, never assume things.

 

[BobP]

I'll have to try out the GFCI to GFCI again, don't see why it wouldn't work. I have some inline outdoor style extension cord GFCIs at home so it's easy to do.
I already plug GFCIs into GFCIs now and it works, new small appliances have built in GFCIs at the cord ends, like hair dryers and portable heaters I use both, never had one trip on me either at the wall GFCI or at the plug end. I also have a 5k btu window AC I use on the boat that has a GFCI end plug, and I plug it into a GFCI outlet on the boat - works fine.

All the outlets on my boat are GFCI protected, even the ones dedicated from the inverter and remoted located.

On grounding, even if all the grounds are in place, one's safety isn't protected to save one's life since very little currect is needed to electrocute, vs. trip the breaker. Very little will trip the GFCI however, that's why it is effective. I believe 20 ma or so trips it, vs. 15 A typical small panel breaker. And the 15 a breaker doesn't trip at 15 amps, not right away anyway, may take somw time to clear.

GFCIs alone are not good enough anymore today hence the creation of arc fault breakers. An arcing wiring fault, most typical kind of fault there is, is another that can well be below the breaker rating to trip the breaker, don't get detected by GFCIs, but more than enough currect to start a fire and burn down a house and the people in it.

I believe home construction laws were changed to include arc fault protection in home construction - for bedrooms and the like.

I added all of this not to have anyone else who reads it believe good grounding is going to save their lives from electrocution or fire, it aint's so - false sense of security.

And the Honda generator is more than enough to finish us off !

I prfeer to go with a rod in my hands, fishing rod that is!

 

[ahill]

New code requires arc fault interrupter on bedroom circuits.
My Honda has a 3 prong plug but it seems the question is one of ground. My batteries are grounded through motors although I've been told an additional ground to a dynaplate saves zincs and othe metals.
I'll try my Honda dealer to see if they have an answer. I Thought that someone on the site may have experienced the problem. If not, it must be unique to my installation.

 

[jehines3]

It not a unique problem. It has to do with the inverter technology used in the Honda design. They use an inverter set-up as it allows them a much lower idle speed in eco mode. Pretty smart, they even have very clean sine wave output. I've never personally tested it as I don't own a Honda. I'm thinking of getting one for AC while on the hook, but the $1000 price tag for such a small unit hurts. My 5200Watt Generac was had for $600 and can power my whole house in a storm, but it is loud as heck. I've seen this problem posted on Boat US also. I'd love to test it, but Not at spending $1000 for another Genset. jh

 

[ahill]

There is a ground connection on the 2000 panel. I'll try that.
Mine runs on eco switch & powers the 5,000 BTU A/C, charger and small loads on galley outlet.
I haven't tried a microwave, Fridaddy or coffeemaker though. From hurricane exp. I know they draw a lot.
Quiet is a virtue on board.

 

[haskindm]

GFCI's trip when they detect a current imbalance between the hot and neutral of 5 milliamperes =/- 1 milliamp. As others have said they do NOT need a ground to operate. There is no reason that a GFCI will not worked when plugged into another GFCI. Many large services have GFCI protection on the Main (for equipment set to trip at about 30 milliamp imbalance) and then standard GFCI's on the branch circuit. The only problem with multiple GFCI's is that when they trip they must be reset in sequence (upstream GFCI's must be reset before downstream GFCI's can be reset) and this causes confusion.

 

[BobP]

ahill, if nothing trips out ignore the flickering.

If you have a Blue Sea panel or Panetronics panel, why not email them and ask question as you posed it here?

Let us know what they say.

 

[jehines3]

ahill, if nothing trips out ignore the flickering.

You realize what the reverse polarity light means right? That is a potientially fatal suggestion without further testing.

I'm not going to suggest using or not using the system. If you are going to, make sure you test the potential between the boats negative DC and AC neutral. Test the potential between the ground bar and the neutral bar. Test the potential between the Hot and Neutral. It could all be nothing, but it only takes mA's to kill someone. jh

 

[BobP]

Good point, however, and there is always "however" - a clarification is called for.

There is no subsititute for proper wiring technique, which is unrelated to a light bulb, being on or off, dead, flickering, or even having one at all.

Since the member is responsible for his actions in terms of safety, then he is not to count on a light bulb to find out what the proper wiring technique is including how to connect portable power. There is plenty of wasted tax money going to the court system to cover people blaming other people for their faliure to be responsible for their own actions.

We are making assumptions that the member is a competent DIYer and that he knows how to properly do what he did. Otherwise he should not have taken on the task himself and instead hand it off to a professional.

You will see that I did indicate to contact the manufacturer of the panel to find out the meaning of "flickering", which no one here knew what exactly it means.

If I did the job as a DIY, I would have wired the boat properly from the get go, connected the generator properly from the get go, with no risk or safety to any person. Otherwise, I had no business doing it. So, the flickering light doesn't change the work I did nor anyone's safety.
If the panel manufacturer didn't care to respond, then I would have done exactly what I advised, ignore it.

Each member is responsible for what advise they follow. As in my case on this site I represent myself as a DIYer, I am not a professional on this site. The member has no recourse to take legal action against me, on the otherhand, in your case, he can. Keep your liability insurance payments up to date.

Irrespective of what the legal aspects are of offering advise, my advise is always directed at competent DIYers and is never something I wouldn't do myself and based on decades of experience. No one is obliged to follow my advise and is free to ignore it. For myself, there is no profit nor loss associated with whatever I write here.

 

[jehines3]

For those unfamilar with the reverse polarity light.

1) AC does not have polarity (we can clear that right up, it is a stupid name for this light)
2) Reverse polarity light indicates that the hot and neutral are swapped.
3) By reversing the hot and the neutral the AC circuit will still appear to work on some circuits. Those with bonded neutral and grounds will be a huge problem as the crcuit breaker may not interrupt.
4) By reversing the circuit you have lost the ability of a circuit breaker to properly disconnect power to work in a safe deenergized state.

See this short tid bit.
http://www.boatus.com/boattech/TipReversePolarity.htm

 

[BobP]

So what's the dictinction between a fully lit light, and the same one flickering ?

Does he have a reverse polarty state, yes or no?

All must be carefull on the troubleshooting advise given to be measuring the AC voltage system, if not done right, you may light up, or worse.

 

[jehines3]

As an average boater I think he has a floated neutral. I looked at the Honda wiring diagram and there is no where shown that the neutral and the chassis ground reference are tied together. Since I did not test his install I take no liability on this one.

The flickering is likely a result of voltage build up on the neutral. You can't light a reverse polarity light without a real voltage potential between neutral and ground being present....jh