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      Abbreviated rules   07/28/2017

      Underdawg did an excellent job of explaining the rules.  Here's the simplified version: Don't insinuate Pedo.  Warning and or timeout for a first offense.  PermaFlick for any subsequent offenses Don't out members.  See above for penalties.  Caveat:  if you have ever used your own real name or personal information here on the forums since, like, ever - it doesn't count and you are fair game. If you see spam posts, report it to the mods.  We do not hang out in every thread 24/7 If you see any of the above, report it to the mods by hitting the Report button in the offending post.   We do not take action for foul language, off-subject content, or abusive behavior unless it escalates to persistent stalking.  There may be times that we might warn someone or flick someone for something particularly egregious.  There is no standard, we will know it when we see it.  If you continually report things that do not fall into rules #1 or 2 above, you may very well get a timeout yourself for annoying the Mods with repeated whining.  Use your best judgement. Warnings, timeouts, suspensions and flicks are arbitrary and capricious.  Deal with it.  Welcome to anarchy.   If you are a newbie, there are unwritten rules to adhere to.  They will be explained to you soon enough.  

GTom

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About GTom

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  1. Lead crystal batteries?

    That's very interesting and a bit difficult to believe, simplest, cheapest = best? How much heeling do these flooded cells tolerate? Lead crystal is costs about 30% more than an equivalent AGM/gel.
  2. Lead crystal batteries?

    Correct, but those are not practical products for the everyday yachtie. Quality gels rarely go above 600 cycles - still no concern if you sail only <100days a year.
  3. Lead crystal batteries?

    Right, I go with a full cockpit tent.
  4. Lead crystal batteries?

    That's why you decorate your bimini with a 310Wp, 220EUR cost solar panel.
  5. Lead crystal batteries?

    That would be really interesting although not at LiFeYPO4 prices. Also 2V/500Ah units are a pain, I don't intend to buy 500Ah capacity for a 30' boat.
  6. Lead crystal batteries?

    Haven't done the maths but probably a single 250Wp panel on your bimini could top up that 15% you need as "slow charge".
  7. Lead crystal batteries?

    Agree with that! The effective costs are very similar, the actual use/abuse will decide your final budget. Replacement cycle/service life is also very usage dependent, heard about well kept quality gel units running after 8-9years... Right, that's where a solar panel comes in the picture.
  8. Lead crystal batteries?

    No, it is NOT, that's what I am trying to explain... On a boat you DON'T deplete your bank to let's say <30% SOC. Not just at night, you need VHF, Chart plotter at broad daylight too. And if you don't, what is the advantage of LFP at a ~3x price? If you understand what the Peukert effect is, then you know how much of an issue is in case of 0.05C load.
  9. Lead crystal batteries?

    You'll have more to worry about than your wallet if you're left without lights, radar and even chart plotter in a busy channel at night. 20% means how much reserve if your engine fails, 2 hours?
  10. Lead crystal batteries?

    SOC=0% IS the safety concern because you can't run your instruments, vhf, lights. Being close to it means risk.
  11. Lead crystal batteries?

    Are there any reliable controller options for a Rutland 1200 windgen+solar? Did any big cruise ships change to lithium? They are profit driven businesses, if really lithium is the way, they should have moved in that direction I suppose. As for price: yes, LiFePO is pricey, the only sane pricing I saw were the Winston WB-LP12V90AH, costs 480$+VAT. That amount of money buys you 250Ah worth of quality gel. I doubt that the lithium option is more than 2.6x better in realistic conditions. One argument for Lithium is that lead is plagued by Peukert's law. Indeed it is, but that begs the question: how many hours of reserve you want in a passage making or any off-the grid boat? Do you really want to minimize your bank that it can be depleted in <5hours? (discharge current >0.2C) Do you really want to risk getting close to 0% SOC (=no lights/instruments, etc) as a routine? Because as I understood, these are the situations where lithium shows its teeth. No problem for a commuter car, but crosses many safety and sanity guidelines for off-the grid cruising.
  12. Lead crystal batteries?

    That's my impression to and leaning towards quality VRLA's at a more realistic price point. LiFeYPO4 is interesting but charging lithium is a pain and they don't live longer than 10 years either.
  13. Lead crystal batteries?

    Apparently nobody heard about them... Short summary after doing the homework: cycle life at 60% DoD, 25°C: ~2200cycles (Sonnenschein claims for their quality gel batteries around 800Cycles), Peukert's law still applies, and the coefficient is in the same range as AGM's. Claimed service life around 12 years at 25°C, more at lower temperatures. Datasheet. And a tech review - latter disputes the longer service life. If every bits are true, the deeper cycles, longer life might worth the additional ~30% cost.
  14. Thank you for the feedback! I have an alternative boat choice that needs a new engine (price is correspondingly lower) - it seems then, Solé/marinized Mitshu is absolutely a viable option! In case I do the engine upgrade I considered Bukh (DV36), but that seems a bit pricey for the task...
  15. Anyone upgraded to lead crystal batteries? I can't find relible 3rd party comparison to AGM, only marketing claims.