Connect with us

portable generator

Discussion in 'Boat Electronics' started by [email protected], Apr 18, 2004.

Scroll to continue with content
  1. Guest

    How can I ground a 1000 watt Yamaha portable generator( EF1000is) to a
    boat ?
  2. Why ??
  3. Ed

    Ed Guest

    If this is for any purpose besides a temporary electric need like
    powering Christmas lights for a one time boat parade I would suggest
    rethinking your whole strategy.... or name me in your will....

    portables and marine gensets have almost nothing in common, except the
    fact that they both make power.

    If it is for a one time activity on CALM water..... may I suggest you
    put it on the SWIM platform (Fuel leaks can ruin your whole day... or
    life) As far as grounding.... they usually have a grounding lug on them.
    Just attach a wire from that lug to the ground of your boat. Not sure
    why you would want to do that. you cannot combine power from multiple
    gensets to power one large item. (Unless they are synced.... impossible
    with a portable genset like you are talking about)
  4. Guest

    Please help me understand. MyYamaha manual says" be sure to ground (
    earth) the generator" and the picture is showing a wire connected to the
    generator and the other end is a nail burried to the earth ground. How
    to I do that on a boat?
    I have a 26 foot Monterey with shore power.I purchased a boat shore
    power adapter to regular household plug ( 3 prong) and I was thingking
    of pluging that to the generator. I am confuse about grounding of the
    generator to the earth ground ( the nailing to ground thing) ????
  5. Well you might be getting out of your depth a bit :) but if the earth pin
    of outlets on the generator are bonded to the neutral then the adaptor
    should be OK. If not then the ground connection on the genny should be
    conected to the earth on the board on your boat.
    Since you seem a little unsure it might be safer to get a little
    proffesional advice.
    With regards to earthing on boats, it is a lot deeper than most are aware
    and long term effects in the form of electrolysis can cause real damage.
    If you are just going to bring the genny aboard now and then IMHO I would
    not be too concerned about the earthing situation since the supply (The
    genny) is independant from the mains and would be very much like "double
    insulation" with regard to earth faults.
  6. Jim Thompson

    Jim Thompson Guest

    I have never understood that issue either. I have been on the edge of
    buying a portable generator for several years, but never got around to
    it because we rarely need it. Meanwhile I have been researching that
    question on the net and in books like Nigel Calder for years too, and
    never found a practical answer Surely there is a simple recipe for
    non-electrrician boaters like us?

    Our boat has an AC shore power 3-pronged inlet socket. We have a big
    yellow 30-amp shore power cable, wihch of course we cannot use with a
    portable generator like Romeoo's: such generators typically output
    electricity through a normal household outdoor 3-pronged extension
    cord. I have a 30-amp pigtail shorepower adapter that can be used to
    adapt the household extension cord to the boat's shore power inlet

    Our boat's AC wiring presumably is independent of the boat's DC
    wiring. Or at least I certainly hope it is. The DC system's ground
    is the battery/engine block. We have no "ground" to the ocean, nor
    would I want stray current in the ocean around my boat.

    Say I'm at anchor. If I put the generator on the swimdeck, run the
    landlubber extention cord to the boat's AC input plug (with the
    pigtail adapter), and turn on the generator, then where is ground? Is
    it necessary to emulate the nail in the dirt, as if setup in a
    campground when powering an RV?

  7. Ed

    Ed Guest

    For short term use, you should be fine from a grounding point of view.
    The round pin on the standard plug is the ground and that should carry
    the ground to the boat. There are many other dangers here you should
    consider that the grounding will not solve... including but not limited
    to: Fuel issues, shock issues, CO issues, etc.
  8. Jim Thompson

    Jim Thompson Guest

    Thanks for the reply. Fuel, CO and other non-electrical issues aside,
    what did you mean by shock issues? And how does the round pin carry
    the ground to the boat, if the boat is fibreglass, sitting on water,
    and the generator is connected to the boat's shore power plug with a
    3-wire shore power cable? Where does that round pin ground lead to?
    Thank you for any insights you can provide to this issue.

  9. Ed

    Ed Guest

    All metal (on most boats) is bonded together (green wires). This
    includes the outdrives, shafts, thru-hulls etc. The bonding wire is
    usually connected to ship's ground (Negative battery) and to the Green
    side of the 110/220 sytem. SOMETIMES... there is a device that sits in
    the middle to help save your zincs in areas with lots of current in the
    water... this aside... the Ground wire on your shorepower is connected
    to the bonding system.

    As far as shock issues... if you touch a hot wire... or are on the swim
    platform when a wave hits you and the generator... or if the plug gets
    wet and you touch it (or any number of things...) you will get
    shocked.... GFIs help but will not eliminate the issue.

  10. WaIIy

    WaIIy Guest

    I always heard you NEVER mix the AC and DC ground together. Never.

    Of course, I'd like to know if this is true, but it makes a lot of sense
    not to.
  11. Jim Thompson

    Jim Thompson Guest

    I was under the same impression. I thought that my AC system was
    grounded through the shore power plug to the 3-wire system ashore.

    Here is my rudimentary understanding:

  12. WaIIy

    WaIIy Guest

    It is, but I don't think your DC system is. I'm sure one of the
    electrical types will render an opinion shortly.

    While they are at it, maybe someone can explain the pros and cons of
    bonding the neutral and ground together in a 120 vac system.
  13. I always heard you NEVER mix the AC >and DC ground together. Never.
    You guys have bumped into the "green wire controversy". Some "authorities"
    say you should not connect AC and DC systems. Charles Payne is of this
    opinion in his book. I'm not sure, but I think Nigel Calder also thinks its
    a bad idea. On the other hand I think Dave Gerr recently had an article in
    Sail or Cruising World in which he said they should be connected together.
    I think this may also be the current ABYC recommendation. The rational is
    that if you somehow get 110V AC into your DC system you can be electrocuted
    by touching the DC if it has no earth ground. Personally I think the
    chances of getting AC into my DC system are so low that I intend to leave my
    systems as the original manufacturer installed them, ie. separate.
  14. WaIIy

    WaIIy Guest

    Thanks for the info. I found a bit of stuff....

    AC Ground
    See Practical Sailor August 15, 1995 for a detailed treatment of the
    green wire. The best solution is a heavy and expensive isolation
    transformer. The acceptable solution (for the rest of us) is to install
    a light and inexpensive Galvanic Isolator in the green wire, between the
    shorepower cord socket on your boat, and the connection to the boat's AC
    panel. Then, connect the grounding conductor (green) of the AC panel
    directly to the engine negative terminal or its bus. Note that this
    meets ABYC's recommendations. In choosing Galvanic Isolators, make sure
    that you select one that has a continuous current rating that is at
    least 135% the current rating on the circuit breaker on your dock box.
    Certain Galvanic Isolators (e.g. Quicksilver) include large capacitors
    in parallel with the isolation diodes, which in certain situations
    theoretically provide better galvanic protection. Unfortunately, these
    units cost substantially more than conventional Galvanic Isolators. If
    you feel like spending real money on galvanic isolation, you might as
    well do it right and buy an isolation transformer.
  15. Yes, there is lots of info out there.
    In my original post I mentioned Charles Payne. Actually the name is John C.
    Payne and the book is "Boat Owners Electrical and Electronics Bible". He is
    against connecting the two systems. This is a fairly old book though.
    I checked my Nigel Calder books and he basically points out the benefits and
    the problems. He concludes that you shouldn't connect the systems unless
    you use a galvanic isolator or isolation transformer.
    I suppose before galvanic isolators became readily available the general
    consensus was to leave these two systems unconnected. Adding the isolator
    and grounding the AC system to the DC system gives you some extra safety
    provided the isolator and its circuit continues to function as intended so I
    guess the current thinking is to go this route.
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day