Running a generator on a boat?

[Matt Lillie]

Re: Running a generator on a boat?

There is enough ambiguity on this topic that I've decided to pass on the job, and will advise the client to use a bullhorn.

Thanks all-
Matt

 

[RYAN LOUDMUSIC JENKINS]

Re: Running a generator on a boat?

Just to throw another wrench into the mess here....If you measure the output of the smaller EU series generators, they have a somewhat balanced AC type of output. They are 60 volts hot to ground, 60 volts neutral to ground and 120 volts hot to neutral. I am no expert on this but I do not think that you could bond the neutral to the ground in this situation.

 

[Bennett Prescott]

Re: Running a generator on a boat?

Just to throw another wrench into the mess here....If you measure the output of the smaller EU series generators, they have a somewhat balanced AC type of output. They are 60 volts hot to ground, 60 volts neutral to ground and 120 volts hot to neutral. I am no expert on this but I do not think that you could bond the neutral to the ground in this situation.

How are they going to work as home backup generators then? When you tie into your home panel you can bet that neutral and bond will be grounded...

 

[RYAN LOUDMUSIC JENKINS]

Re: Running a generator on a boat?

Bennett, I don't have an answer to that but this only applies to the smaller units that are 120 volt only. I have personally measured the 2000s and 3000s. None of the 240 volt units have measured like this for me but I have also never used any of the larger inverter generators, only the EU3000s and smaller. All of the larger 5500+ Honda generators I have used have been old school Non-inverter generators..

 

[David Buckley]

Re: Running a generator on a boat?

How are they going to work as home backup generators then?

You can't, not without modding the generator, or using a transformer.

I have a genset just like that, it's a dual voltage generator, in that it can supply either 240v or 120v, and both are centre tapped.

In 110v mode it is compatible with the UK building site standard, which is 55-0-55 so a phase to earth shock is 55v.

None of the many generator grounding or voltage arrangement is bad or good, they are just different and need to be understood in the context on how you want to use the genset.

For this specific boat example, using a genset with RCD/GFCI outlets i'd be tempted to bond the ground pin of the genset outlet to the boat ground terminal which should be the same as the boat metalwork. For a temporary setup this seems to offer the best chance of a safe setup.

E2A - if you are running with a centre tapped supply one wiggle is that there are usually protective fuses in just the hot line, but with a centre tapped supply you have two hots and no neutral. Again not a big deal on a temp rig using RCDs and puny generators, but it is something to be aware of with bigger systems (eg "balanced power") with more fault current potential.

 

[TJ Cornish]

Re: Running a generator on a boat?

It's unclear to me - even after fairly substantial research - if the EU2000 and EU3000 actually are balanced power, or if the ground is just coupled in some fashion such that it appears to be 60V H->G and N->G. If it's balanced power and bonding N ->G will cause improper generator operation, I don't understand how the receptactle does not have to be a GFCI. A ground that doesn't go anywhere defeats the purpose of having a ground at all.

 

[Jason Lavoie]

Re: Running a generator on a boat?

It's unclear to me - even after fairly substantial research - if the EU2000 and EU3000 actually are balanced power, or if the ground is just coupled in some fashion such that it appears to be 60V H->G and N->G. If it's balanced power and bonding N ->G will cause improper generator operation, I don't understand how the receptactle does not have to be a GFCI. A ground that doesn't go anywhere defeats the purpose of having a ground at all.

For an inverter, making balanced power is easier (cheaper) than making one 120v leg.. I would suspect that any inverter based device that isn't forced to have neutral bonded to ground will work this way. and no, it probably won't be happy with neutral tied to ground. (found this out the hard way with my first big 12V-120V inverter)

Jason