Replace the genset with an inverter

Discussion in 'Electronics Q&A' started by Happy Feet, Jun 29, 2022.

  1. Happy Feet

    Happy Feet New Member

    4
    Jun 29, 2022
    2007 Sea Ray Sundancer 340
    Mercruiser 8.1 vdrives
    At this point, shore power. Could change out alternator at a later time.
     
  2. dtfeld

    dtfeld Water Contrails GOLD Sponsor

    Jun 5, 2016
    Milton, GA
    410 Sundancer
    2001
    12" Axiom and 9" Axiom+ MFD
    Cat 3126 V-Drives
    Have you priced out those systems? They are not cheap either, and your looking at a complete rewire of the DC system.

    count me in the rebuild/replace the generator first. A nice inverter system after that would be best of both worlds, but Sea Rays are power hungry beasts, that really need a generator first and foremost.

    what is wrong wit the generator?
     
  3. Happy Feet

    Happy Feet New Member

    4
    Jun 29, 2022
    2007 Sea Ray Sundancer 340
    Mercruiser 8.1 vdrives
    Gone from a run time of 15 minutes to no power for start. Had the impeller bypassed by a electric pump to run cooler. It worked well until the no power issue. Having issues getting a mother board.
     
  4. b_arrington

    b_arrington Well-Known Member GOLD Sponsor

    Feb 21, 2007
    Setauket, NY
    Back Cove 37
    AB Ventus 9VL
    Cummins QSC 8.3 600
    Just consider I t’s going to take a long time to charge all those batteries at 30A, or even 50A. Marine infrastructure isn’t yet setup for battery bank recharging.

    Not much chance of an alternator having enough capacity to charge a bank that big.
     
    dtfeld likes this.
  5. dtfeld

    dtfeld Water Contrails GOLD Sponsor

    Jun 5, 2016
    Milton, GA
    410 Sundancer
    2001
    12" Axiom and 9" Axiom+ MFD
    Cat 3126 V-Drives
    The nice thing about LiFePo4 chemistry is you can charge it very fast at a high C rate with multiple sources, but if you think your going to charge that up the next afternoon with a solar panel, think again!

    Regardless, I don't see how you could charge that big a battery without a huge charging system and event then, you will be spending 1/2 a day minimum getting it done.
     
  6. jmauld

    jmauld Well-Known Member GOLD Sponsor

    Jun 9, 2020
    Carolina Beach
    2010 Sundancer 390
    2016 Sea Hunt Ultra 211
    Twin 8.1l of gas guzzling iron
    There’s room above a large camper canvas to maybe get 800w of solar panels. That could get you 4kwh of power each day, which would be enough to run most of the DC loads, including the fridges. Might be worth it in a more moderate climate. Biggest challenge would be making it look decent. It’s that power hungry AC that kills most of these ideas. :)
     
  7. ttmott

    ttmott PhD in OCD TECHNICAL Contributor GOLD Sponsor

    Apr 3, 2012
    Space Coast Florida
    2006 52 Sedan Bridge
    Cummins QSM11
    "could" is the right term - On an average the best of panels are 60% effective; shadowing and sun angle being the determining factors. Consider panels on boats are almost never consistently at an optimum angle to the sun.
     
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  8. ttmott

    ttmott PhD in OCD TECHNICAL Contributor GOLD Sponsor

    Apr 3, 2012
    Space Coast Florida
    2006 52 Sedan Bridge
    Cummins QSM11
    Charging with engine driven alternators are a good way to go but the alternator charging system must be set up to accommodate the high charge rates that the low resistance batteries will demand. 0.5C (even less) on a large battery bank will most assuredly destroy any OEM alternator configuration. One would need large Balmar alternators with external charge controllers, temperature monitoring, and specialized belt drive configurations. It's expensive...
    Certainty, an external charge controller can be adapted to the OEM alternator, but the charging timeline would be quite excessive. It is a great configuration for distance cruising where time is of no consequence. 120 Amp OEM alternators with external regulators can be set up to safely output 60 to 80 amps continuous with temperature monitoring. Let's say two alternators providing 60 amps continuous and they are balanced (Balmar Centerfielder) so it is a true 120 amp output and your battery bank needs 1500 Ah to full charge then you can see that is 12.5 hours of charging; and, that is only the bulk charge phase.
    Again, this is where a gas/diesel powered generator becomes an effective supplemental power source.
     
    Last edited: Jul 1, 2022
    Chris-380 likes this.
  9. jmauld

    jmauld Well-Known Member GOLD Sponsor

    Jun 9, 2020
    Carolina Beach
    2010 Sundancer 390
    2016 Sea Hunt Ultra 211
    Twin 8.1l of gas guzzling iron
    I accounted for the 60% effectiveness in my calculation :). The problem is that those who would produce the most power from solar also need an AC which means the solar wouldn’t make much of a dent in their power needs.

    my dockmate with a blow boat has added enough solar that he no longer has to plug into shore power except for when he wants to run the AC. He is able to keep his batteries charged and run all of his other loads. He did this out of spite to the Dockmaster who implied that they “guess at the meter usage”. He has a catamaran so he has a lot more overhead room.
     
    Last edited: Jul 1, 2022
  10. dtfeld

    dtfeld Water Contrails GOLD Sponsor

    Jun 5, 2016
    Milton, GA
    410 Sundancer
    2001
    12" Axiom and 9" Axiom+ MFD
    Cat 3126 V-Drives
    One other thing if going all in on Solar. Is you have to derate based on the angle to the sun, but also, your real production of electricity is limited to about 4-5 hours a day.

    800W on the roof, might produce 2000-2500w on a good day. It’s just not possible to optimize these on a boat subject to wind and currents.

    The other part of the equation is power consumption. If your just running some household appliances for a few minutes each, watching some TV and topping up batteries, this is probably workable.

    Heating and cooling on solar and a boat, no way.
     
  11. jmauld

    jmauld Well-Known Member GOLD Sponsor

    Jun 9, 2020
    Carolina Beach
    2010 Sundancer 390
    2016 Sea Hunt Ultra 211
    Twin 8.1l of gas guzzling iron
    My biggest distractor to solar is, it’s ugly and doesn’t go with the lines of our boats at all. The greenline boats are able to incorporate solar into their roof lines.
     
    dtfeld likes this.
  12. ttmott

    ttmott PhD in OCD TECHNICAL Contributor GOLD Sponsor

    Apr 3, 2012
    Space Coast Florida
    2006 52 Sedan Bridge
    Cummins QSM11
    It's more of a practical / and cost vs return thing. peeing in the ocean comes to mind with large battery banks like the OP is alluding. Maybe a large power-cat and the acreage available could benefit....
     
    dtfeld likes this.
  13. dtfeld

    dtfeld Water Contrails GOLD Sponsor

    Jun 5, 2016
    Milton, GA
    410 Sundancer
    2001
    12" Axiom and 9" Axiom+ MFD
    Cat 3126 V-Drives
    I have contemplated adding flexible solar on top of my camper. Sailrite had a nice video on how to do it, and on my set up it would be almost invisable.

    However, there are a host of issues that go along with something like that...not convinced its worth it unless a fun sewing project for myself.
     
  14. jmauld

    jmauld Well-Known Member GOLD Sponsor

    Jun 9, 2020
    Carolina Beach
    2010 Sundancer 390
    2016 Sea Hunt Ultra 211
    Twin 8.1l of gas guzzling iron
    There’s also use case to consider. A Sundancer isn’t as likely to be used in the same way that you would use your sedan bridge. It’s going to sit at a dock for the vast majority of the time and taken out for the weekend. It could provide a meaningful charge over a 2-3 week period. Another use case is just to keep the batteries topped off while idle. I have a small panel on my T-top and haven’t had to top off that battery 3 years now. It keeps the bilge pump humming along nicely no matter how much rain we get. Previously, there were instances where the bilge pump drained the battery in heavy rains. (It’s a poorly designed boat)
     
    b_arrington, firecadet613 and dtfeld like this.
  15. jmauld

    jmauld Well-Known Member GOLD Sponsor

    Jun 9, 2020
    Carolina Beach
    2010 Sundancer 390
    2016 Sea Hunt Ultra 211
    Twin 8.1l of gas guzzling iron
    I’ve seen that, but I’ve never seen anyone that reported having a good experience with flexible panels.
     
    dtfeld likes this.
  16. dtfeld

    dtfeld Water Contrails GOLD Sponsor

    Jun 5, 2016
    Milton, GA
    410 Sundancer
    2001
    12" Axiom and 9" Axiom+ MFD
    Cat 3126 V-Drives
    Exactly.
     
  17. Eric Pawelski

    Eric Pawelski New Member

    4
    May 14, 2022
    1988 SeaRay 44
    454 x 2
    I'm in need of a governor from the generator, if you interested in selling it let me know Eric 941 264 4070
     
  18. GnrlPatton

    GnrlPatton Well-Known Member PLATINUM Sponsor

    599
    Jul 12, 2010
    Maple Valley, WA
    Current: 1998 370 Express Cruiser
    Sold:1988 230 Weekender
    Twin Cat 3116T
    I have 2 100W flexible panels on the rear of my hardtop. The most I've ever seen was about 130W, and that's when the sun is directly overhead to the stern. I'm more typically in the 50-100W range on a good day. I went in with higher expectations than I should have, I'm not sure I would go with solar if I were to do it all again.

    I am now building out a DIY LiFePo install, I have all the pieces for it (3x 304AH banks and all Victron equipment), and am now setting it up on the bench to work through all of the details before even considering installing it in the boat. Even with that in place, I would still expect to have to run my generator at times if I'm out for more than 3-4 nights, and that is without running my AC.
     
    dtfeld likes this.
  19. dtfeld

    dtfeld Water Contrails GOLD Sponsor

    Jun 5, 2016
    Milton, GA
    410 Sundancer
    2001
    12" Axiom and 9" Axiom+ MFD
    Cat 3126 V-Drives
    How are you assembling the 304s? I tried a couple different ways, but finally bit the bullet on 2 Sun Fun Kits, and got the installed this week. I’m pretty happy with them.
     
  20. techmitch

    techmitch Well-Known Member PLATINUM Sponsor

    May 1, 2008
    Chesapeake Bay, Middle River/Frog Mortar Creek MD.
    1999 270 DA
    Twin 4.3s W/Alpa I Gen II's
    I don't think a governor from a 2007 340sda will fit your quick silver 8kw.
     

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