T-Pain Is On A Boat: RE: [Electric Boats] Re: An Electrical question on a boat [1 Attachment]

Tuesday, June 7, 2011

RE: [Electric Boats] Re: An Electrical question on a boat [1 Attachment]

[Attachment(s) from Steve Dolan included below]

Hi Pat and Eric,
Sorry guys I didn't get back sooner, was in Boston for the birth of our first grandchild for a few days. Another swabby in a few years. :o)

If I got this right your both saying that I have to interconnect the 2 separate grounds to the one ground from the Echo box which kinda made sense from the start. The reason Pat I need a separate charger when the Genset isn't running is a parasitic voltage gauge that's in the control circuit of the Genset. Once the Genset is running the Alternator will top off and maintain the charge of the 1 battery. See attached drawing.

Eric,
Educate me, why does the Propulsion bank need an independent ground?

Thanks for the help guys,

Steve in Solomons MD
410SE Lagoon Electric Cat

Hi Steve. It sounds like you've got 3 battery banks. The propulsion bank, the house bank and the starting bank (one battery). ABYC says that the propulsion ground must be seperate from other systems.

I don't see any issue with combining the ground of your house and starting banks assuming that they are the same voltage. Using one of the battery combiners like the Xantrex Echo requires a common ground. Like you, I believe that using a combiner to charge the starting battery any time that the house bank is being charged is the most elegant solution. By isolating the starting load to just the genset battery, your house loads won't see the starting voltage drop. It should also guarantee that the genset will have enough power to start regardless of how low the house batteries get discharged.

Fair winds,
Eric
Marina del Rey, CA

--- In electricboats@yahoogroups.com, Steve Dolan <sdolan@...> wrote:
>
> Hi Pat,
> "IT" was the Genset start draw on the battery (At the time the house bank). The electronics would temporarily shut down do to power draw on the bank. I also didn't understand why it would make a difference. Hope that helps clear "it" up. :o) As for the second part of the question I wasn't sure if the Genset battery would charge without a combined ground to the house bank. When I'm done I'll have a complete set of diagrams for the next owner, something few boats/manufactures provide at the start and always a good idea for electrics.
>
> Again thanks!
> Steve
> 410SE Lagoon Electric Cat
>