Just heard about this. Wiring the earth ground to the neutral leg of the 110v output on a Honda 2000 generator. Seems to eliminate false polarity indications when feeding power into house panel. If this is a good idea, why didn't honda provide for it?
Earth Grounding Honda Generator
- Thread starter gettinthere
- Start date
I can see one reason: ungrounded neutral is WAY safer than grounded. If it's ungrounded, the only way to get a shock is if you're touching BOTH hot and neutral. If it's grounded you just have to touch hot and any ground. Unfortunately most appliances, etc. ground the neutral anyway so it gets grounded and becomes unsafe.
druid
druid
I can tell you that Honda does not officially endorse the use of their generators for boating purposes because of possible liability reasons. They have instructed their dealers to avoid any product claims, advertisement or support for the use of the generators in the marine environment. They are aware they got the market but will not acknowledge it. I had the issue with the reverse polarity light and resolved it with a piece of electrical tape to cover it.
The neutral and ground must be bonded at the source of newly derived power. That means at the service entrance at your house, every time you install a transformer, or when you use an alternate power source like a generator. The reason is so that your nuetral and ground are at the same potential. If not you could get shocked by touching the Neutral in one hand and a the Ground in the other! Electricity is about the potential (power difference) between two wires not the names of the wires or the colors.
You would also have to actually ground the earth ground also and not just leave it "floating" There is probably no privision for that either.
Bill that happens in houses via the ground rod or rods which are a required part of the service entrance from the utility. In larger and commercial building the building steel is included in this process. I refuse to pay for another rule book to find out what is expected so perhaps Maine Sail can jump in and quote the Yacht Council's opinion on the matter of boat to water grounding.
The simple answer is no. Ground fault devices do not even need to be grounded to work. They work by measuring the difference between the Hot and Neutral wires. When the difference between the two becomes more than a pre-designated amount, depending on the GFCI device, the circuit is opened to prevent any possibility of electrical shock. It is assumed that the power, the difference between the Hot and Neutral, is going to ground and possibly through some unsuspecting person. That is why it is called a "ground fault". Hope that helps.
My marine electric generator is grounded to the auxiliary engine block, and thus to the water. Have no expertise in the dark arts, but remember my ABYC electrician telling me he had moved it there...from somewhere. Works great, haven't lit myself on fire yet!
Uncle Dom did a good explanation of how a GFCI is SUPPOSED to work, but some cheat and just look at the current on the ground wire (Which is REALLY stupid if you think about it...). So a proper one will work correctly whether the neutral is grounded or not.
And his explanation of electric potential is correct, theoretically. In a purely floating system (ie neither AC wire connected to ground), either wire can "float" to many volts with respect to ground (which is why Electric Utilities ground the neutral - there's thousands of volts in the secondary transformer that could impress on the wires). However, on a boat where there's no source of high voltage except the generator, the wires aren't going float up a significant amount, and if connected to ground would not supply enough current to be damaging. So I stand by my assertion that a floating system is safer than an grounded one.
druid
And his explanation of electric potential is correct, theoretically. In a purely floating system (ie neither AC wire connected to ground), either wire can "float" to many volts with respect to ground (which is why Electric Utilities ground the neutral - there's thousands of volts in the secondary transformer that could impress on the wires). However, on a boat where there's no source of high voltage except the generator, the wires aren't going float up a significant amount, and if connected to ground would not supply enough current to be damaging. So I stand by my assertion that a floating system is safer than an grounded one.
druid
Calder, and I believe Don Casey, state, as I recall from memory, that when making AC electricity on board that the boat's neutral and ground wires should be tied together on the AC source (inverter or generator). Your Honda probably has the neutral grounded to the generator case and the output ac receptacles probably has a green, black, and white wire behind it. I believe if you have an isolator on board you would then want the generator case, engine, AC ground bus and DC ground bus all tied together. When hooked up to shore-side AC, you don't want the neutral and ground wires tied together on the boat. Before following this advice, you might want to listen to the experts on this forum.
3 or 4 years ago, I installed an older Onan 7.5kw genset on my boat. The AC output leads were isolated from the genset casing and when I hooked up the house AC circuit to the genset, the reverse-polarity lights went on. Concerned, I posted on a forum seeking advice. I didn't get one response :-(.
Since I have a couple of degrees in electrical engineering (which really means I know just enough to kill me) I decided to tie one side of the onan's AC output to case ground on the genset, making that lead the neutral. The remaining lead became the hot lead. I then wired the hot and neutral leads into my home-made transfer switch which consists of three 3p2t, 90 amp relays. When the relays are energized, the shore receptacle on the boat is isolated and the house hot, neutral and ground leads are connected to the onan, causing the house neutral and ground wires to connect to the onan case. It seems to have worked these past years. I haven't electrocuted my self while crawling through my engine room when the genset is running and connected to the house. I don't get any shocks from my appliances; and, my reverse-polarity tester doesn't light up like a Christmas tree when I plug it into any of my AC wall receptacles. If anyone thinks I am in danger, I'm not too proud to listen to advice.
3 or 4 years ago, I installed an older Onan 7.5kw genset on my boat. The AC output leads were isolated from the genset casing and when I hooked up the house AC circuit to the genset, the reverse-polarity lights went on. Concerned, I posted on a forum seeking advice. I didn't get one response :-(.
Since I have a couple of degrees in electrical engineering (which really means I know just enough to kill me) I decided to tie one side of the onan's AC output to case ground on the genset, making that lead the neutral. The remaining lead became the hot lead. I then wired the hot and neutral leads into my home-made transfer switch which consists of three 3p2t, 90 amp relays. When the relays are energized, the shore receptacle on the boat is isolated and the house hot, neutral and ground leads are connected to the onan, causing the house neutral and ground wires to connect to the onan case. It seems to have worked these past years. I haven't electrocuted my self while crawling through my engine room when the genset is running and connected to the house. I don't get any shocks from my appliances; and, my reverse-polarity tester doesn't light up like a Christmas tree when I plug it into any of my AC wall receptacles. If anyone thinks I am in danger, I'm not too proud to listen to advice.
Yea they are dark arts for sure. the easiest way to think about it is to consider each AC source as a seperate, well source. The AC selector switch should handle all the neutral and grounding issues for you.
Shore power ground goes to the boat AC inlet plug, inverter ground goes t the inverter and generator ground goes to the generator. The source selector isolates each source so they cannot interact with each other
Shore power ground goes to the boat AC inlet plug, inverter ground goes t the inverter and generator ground goes to the generator. The source selector isolates each source so they cannot interact with each other
Just throw the Ground lead over the side a leave it near your zincs. All will be fine....sort of....
We have a Nextgen 3.5 KW generator on our boat so don't use a Honda. I do own a Honda eu2000 and have used it on boats. Honda does recommend it's use on boats, http://powerequipment.honda.ca/generators/inverter-series/eu2000i
Actually when I bought the Honda a few years ago the brochure that came with it had a picture of a sailboat in a slip with an eu2000 on the dock plugged into the boat.
I have a 110 V plug with the neutral and ground terminals connected. It is clearly labeled as to what it is. I keep it in the case with the Honda and plug it into the second outlet on the generator when it is required.
Honda does sell a version of the eu2000 with the ground and neutral connected, I believe to comply with the standards on construction sites in some jurisdictions.
Bob
Actually when I bought the Honda a few years ago the brochure that came with it had a picture of a sailboat in a slip with an eu2000 on the dock plugged into the boat.
I have a 110 V plug with the neutral and ground terminals connected. It is clearly labeled as to what it is. I keep it in the case with the Honda and plug it into the second outlet on the generator when it is required.
Honda does sell a version of the eu2000 with the ground and neutral connected, I believe to comply with the standards on construction sites in some jurisdictions.
Bob