David asks, "what are the real-world/real-life electrical issues with a Honda generator on a boat?"
There are many answers depending on how the machines are used. Along the New York and Canadian Canals, many people have long extension cords. They place the portable generator on shore because it's noisy. They run an extension cord from the generator to the boat to power onboard electrical attachments. That arrangement is not code compliant in several ways, and can place swimmers at great risk. Every time? No. Some times? Yes. Is the risk equation good enough for your grandchildren?
When the genset is used aboard the boat, there are electrical, electro-mechanical, CO, CO2 and gasoline handling hazards. Every time? No. Some Times? Yes. Is the risk equation good enough for your family?
Is there a distinction between emergency and routine use? Most portable generators are intended for emergency applications or construction site use, yes?
As you say, some of the codes do seem arcane and theoretical. Many electrical faults can exist silently in homes and boats, but don't become dangerous until "something else" happens. I would assume a very high percentage of older, multi-owner boats have silent electrical faults aboard in both their AC and DC systems. The codes we're talking about are often designed to anticipate the "something else" conditions that you might never anticipate. For example, to dump AC into the water, you need two faults to be present at the same time. Neither one by itself is sufficient. With most portable generators, located on shore, you automatically have one of the faults. If the other one exists silently aboard the boat, now it can can kill you. Every time? No. Some times? Yes. A chance that's worth taking?
NFPA and NEC in the US, CSA in Canada, and the ABYC for boats, all say that 1) the neutral and safety ground should be bonded together at the "derived source." That is very complicated on boats, where shore power presents different requirements than fixed, permanent on-board generators and inverters. How would the portable generator be treated? Is it "shore power" or is it an "on-board" source? The codes all require 2) the neutral-to-ground bond to be "earthed" at the shoreside derived source. Neither condition is met/meetable by the design of the Honda EU2000 genset. The floating neutral all by itself can be dangerous. And although a floating neutral makes it moot, no one I know ever takes the time to earth a portable generator.
Have their been electrocutions? Great question. Absent tell-tale burns, how do you distinguish an electrocution from a heart attack? The simple truth is, these devices are not made for use on boats and are not designed to be safe on a boats. The manufacturers all tell you that in great big bold letters to distance themselves from liability law suits.
But all that said, many, many people do it.
I only pointed it out yesterday because two posters yesterday suggested doing it to save money; "penny wise" perhaps, but not safe was my point. And IN MY OPINION, not good advice. The nasty truth is, you might well get away with it, and even for some years, at that. But for some small subset of unlucky souls, they won't get away with it.
Jim
more good advise
Check your boat insurance - coverage could be void for using un-approved marine devices which cause damage or insurance claim loss.
FYI - A Honda gen users group: http://autos.groups.yahoo.com/group/Honda_EU2000_Generators/?yguid=159274965
Follow up info:
http://www.cdc.gov/niosh/topics/coboating/
Here's a quote from the site:
"In August 2000, the National Park Service, through the Department of the Interior, requested assistance from the National Institute for Occupational Safety and Health (NIOSH) and the U.S. Coast Guard to evaluate visitor and employee carbon monoxide (CO) exposures from generators and propulsion engines on houseboats. This initial investigation characterized CO poisonings through epidemiologic data gathering and the measurement of severely hazardous CO concentrations on houseboats at Lake Powell. Since that initial investigation, over 800 boating-related poisonings in 35 states have been
identified with over 140 of these poisonings resulting in death. Over 300 of the poisonings occurred on houseboats, with more than 200 of these poisonings attributed to generator exhaust alone.
Initial investigations conducted by NIOSH industrial hygienists and engineers showed very high concentrations of CO on and around houseboats using gasoline-powered generators."
The site has multiple supporting documents and sites to give day/time/place to the hazards of gasoline generators and portable gasoline generators.
Ken
Sounds like an installation or user 'use' problem(s).
Another comment:
To that end, this is a little explanation not intended to demean the
value of the gospel according to IEC or ABYC or any other holy text, but
just to shed a little light:
1. HOW DO YOU GET A SHOCK --- the answer is easy, you simply get
yourself to be the conductive path between two points that have an
electrical potential difference. As long as you are not the circuit
(i.e. path) between two points you are not going to get a shock. That is
why birds and even helicopter-borne service men can work on live wires
with 100,000 volts and more as they are simply touching one point only
and have the air as an insulator to the second point (earth).
2. IF THAT'S THE CASE WHY CAN I GET A ZAP WHEN I JUST TOUCH ONE HOT
WIRE? --- well, the answer is that you can thank the electrical power
grid for that. The earth is a very large and good conductor and the
power grid system uses that as the return path for their system as
opposed to using a dedicated and expensive and potentially faulty wire.
When you touch a hot wire at home or on your boat while on shore power,
you ARE to some degree between two points. If part of your body is well
grounded (feet in damp soil) you will get a lulu of a jolt. If you are
on a high resistance surface, you are less well grounded and you may
feel only a small shock or even nothing, -- but it is not worth taking a
chance.
3. HOW DOES THE GREEN GROUND HELP ME --- well, for example if the hot
wire in your nice metal cased toaster (if you could find such a thing
today) became adrift and touched the metal case and there were no green
ground, the first person to touch it could provide the return path to
ground and thus get a real jolt. If the toaster had a green wire ground
and it was secure to the case, it would provide the ground return path
and be a very low resistance one carrying lots of current and would blow
the circuit breaker thus providing a safety. It would prevent the case
of the toaster case from ever reaching a high enough voltage to shock you.
4. WHY IS AN ON-BOARD THE BOAT GENERATOR NOT A SWIM SHOCK HAZARD ---
quick answer is because it is not designed to use the earth as a
conductive path. On shore power, the black (or red) hot wire looks
first of all to return its current to shore via the neutral white wire.
Failing that, as a second choice it might find a fault and try to return
by the safety ground, which while not permissible situation, is still
relatively safe and not yet a swim hazard IF it is in perfect
condition. However, if it is NOT in perfect condition, then the hot
wire(s) will try for their third option and try to return ot shore via
the the water your boat is in. This might be via a direct link it finds
creating a terrible shock hazard especially in fresh water, OR it might
be via your body to a grounded point in the boat and thence to the
water/earth back to the shore power source. However, a generator on
board the boat will not have this third option since its power output
has never been sourced from an earthed point. The only way that the
on-board generator will present a swim shock hazard is if you ran an
extension cord to another boat and that boat had an open ground and a
path for the hot wire to leak to the water body your in. In that case,
swimming anywhere between the boats would present a shock hazard as
there would be a voltage gradient in the water.
5. SO AM I SHOCK FREE WITH AN ON BOARD GENERATOR --- unfortunately no.
Since ABYC requires that an on board source of AC power be grounded to
the boats ground, an extreme example would be your ungrounded metal
toaster with the hot wire touching the case, and you touching the
toaster case and simultaneously your sink faucet. This would again
"light up your life". The question has been asked what about if you
have a Honda generator on board and you take on cord direct from it to a
freezer. Why one would use a two wire ungrounded cord versus three wire
grounded cord I will never know, but I will say that you would be very
hard pressed to become the return path for any current in that case. I
am not recommending it, but just can not see any feasible way to become
that return path under normal circumstances. Now off to don my asbestos
shorts.
Ken
Ken, I understand why you are explaining it this way, but this goes
beyond overly simplistic and is actually incorrect. Someone taking this
at face value could be at some risk.
Current does not "prefer" one path to another -- it uses ALL available
paths at once. The amount of current in each path will be inversely
proportional to the resistance of that path, but that's different from
"first this way, unless it's broke, in which case that way."
If a neutral wire becomes "open," current will not "try ... to return by
the safety ground." Either the neutral and ground are shorted to each
other inside the appliance, or they are not. If not, then an open
neutral stops the current flow completely. If they are, then current
uses BOTH paths all the time; assuming the wires are the same gauge (not
always -- grounds are generally permitted to be one trade size smaller
than the other wires), then each will carry about half the current,
always. This is known as a ground-to-neutral fault, and would trip a
GFCI if one was present in the circuit.
By the same token, if a hot wire happens to be in contact with a case,
and that case is not itself grounded, then a person touching the case
will conduct some of the current even if most of the current is already
properly returning by the neutral. So an open (or otherwise
compromised) neutral is by no means required or even commonly involved
in most appliance shock situation.
The main purpose of the safety ground, and the reason why it is
MANDATORY that the ground be bonded to the neutral at the source
(whether that be shore power, an isolation transformer, a generator, or
an inverter) is to ensure that a hot-to-case-to-ground fault will
immediately short-circuit and instantaneously trip the breaker
magnetically (or melt the fuse, as the case may be). It is NOT to serve
as a viable alternative return path for actual operating current.
Not trying to be argumentative, just trying to make sure anyone
following along stays safe.
-Sean
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