Click for Burger Click for Glendinning Click for Cross Click for Perko Click for Mulder

Batteries

Discussion in 'Technical Discussion' started by 1000 islands, Jul 16, 2015.

You need to be registered and signed in to view this content.
  1. ranger58sb

    ranger58sb Senior member

    Joined:
    Aug 20, 2013
    Messages:
    897
    Location:
    Chesapeake Bay, USA
    Yep, good point about sunlight.

    Wind generator? (Mostly the loud ones are sort of a pain...)

    Or sometimes you can't get there from here, without changing the game rules. But leaving another dock that has no shore power, anchoring (or just cruising) for a while with genset running and fast charger doing it's thing... might be an example of working around the rules.

    Or sharing somebody else's dock power for a while...

    Maybe other alternatives; just brainstorming a bit...

    -Chris
  2. Norseman

    Norseman Senior Member

    Joined:
    Feb 24, 2005
    Messages:
    3,110
    Location:
    Ft. Lauderdale
    I keep reading the sad story about the fridge discharging a battery.
    No magic or bad news, just numbers:
    The fridge/freezer combo on my sailboat drew 5 amp/hrs when operating.
    I added extra insulation for a total of 4,3/4" in both the fridge and freezer.
    The system would run 10 hrs for each 24. (Day)
    Easy math.
    50 amp/hrs per day.
    Get a better fridge and a few solar panels and you are all set.
    Ne need to ruin big batteries by running them down.
  3. ranger58sb

    ranger58sb Senior member

    Joined:
    Aug 20, 2013
    Messages:
    897
    Location:
    Chesapeake Bay, USA

    Capt J's comment about solar that far north may be spot on.

    My experience with NovaKool is that they're pretty good fridges. DC compressors, etc. The RFU 9000 is pretty big. I see on a different NovaKool chart this time that it uses 5.2 amp/hours when running. So my previous example math is incorrect, but 1000 can re-do that for himself :)

    http://www.novakool.com/products/two_doors/documents/specificationsimperialJuly2015_001.pdf

    I can't tell when our compressors are running, can't hear 'em; they're said to be variable-speed compressors, but I dunno if that means they're always on or not (so my math example further above used 24-hours/day run-time, which may or may not be the case).

    Extra insulation might indeed help, if there's room. Could be a way to cut down run-time.

    -Chris
    Last edited: Jul 22, 2015
  4. Norseman

    Norseman Senior Member

    Joined:
    Feb 24, 2005
    Messages:
    3,110
    Location:
    Ft. Lauderdale
    Maybe I am ****, but I installed digital hour meter connected to the compressor. Hence I could monitor the exact running time per day (24 hrs)
    After 10 year I logged 11,000 hours and had no problems.
    Here is a tip of the glass to the Cool Blue system. Loved it....
    Also had a Battery Monitoring system that showed every amp going in and going out, again: Sit for anchor in the Excumas with cold ice cream and quiet power from the 2 Siemens 75 watt solar panels..
  5. ranger58sb

    ranger58sb Senior member

    Joined:
    Aug 20, 2013
    Messages:
    897
    Location:
    Chesapeake Bay, USA

    Seems like a very useful approach, if compressor run time is critical... as is maybe the case, in "island's" case.

    -Chris
  6. Norseman

    Norseman Senior Member

    Joined:
    Feb 24, 2005
    Messages:
    3,110
    Location:
    Ft. Lauderdale
    Not critical per se, but I installed the compressor hour meter severeal years before the battery monitoring system, hence the hour meter was a good way to keep track of how much the house bank was being discharged.
    Also an indication of the efficiency of the system. I used the "run time" to experiment with different seals to find the one which leaked the least.
    Just using both boxes as a fridge, I was down to 3 hours run time per 24.
    (Spill-over system)
    Using one as a fridge and the other as a freezer, 10 hours.
    To draw down from ambient, freeze ice and cool 2 cases of beer, easily 20
    Hours per day. Each hour was right at 4.5 amp/hour, but rounded off to 5 for easy math and you know what the battery discharge is.
    Later with the battery monitoring system the hour meter was less important, but a good back-up.
    Later again with 2 solar panels up and running, and with a "Solar Booster"
    one could almost forget the hour meter and the battery monitoring system as there was always plenty of juice in the batteries.
    Of course it also helped that I converted every light on the boat, inside and out, to LED. Huge difference. (And big expense)