Comments

  • pickup running lights and trailer
    Our 2017 Ram is the same. Trailer running lights come on with trucks headlights.
  • Battery interconnect cable length variation
    The small variations in length of cables will not be an issue for efficiency or damage.
  • Health Insurance
    Update. It looks like we will be signing up with Zion Health Share. They don't require any specific religious affiliations and work with any doctor at any facility in any state. Seems great for FT travelers.

    Cost is WAY less at $515/month for both of us with essentially a 1000/incident deductible after 3 incidents (god forbid) they cover 100%.

    It will be nice saving almost 1300/month. This was a major budget consideration for us..

    https://zionhealth.org
  • Stickers! What do you do with them?
    We were at Wall Drug yesterday.
  • softstart
    Yes, on both of our AC units. They make a big difference in the inrush amperage. Our Coleman units were suppled without any start caps at all so they were very unfriendly to our inverter starting up. Our 4000 watt inverter would start one with a fault light on the remote and wouldn't start the second with the other one running. After installing the micro air soft starts both units start easily. No fault warning.
  • Wet Bay Mod and Filter Add
    I ended up replacing the camco pressure reducer which had poor flow with a better unit and added a second meter on the black flush with allows me to add water to the black tank from the outside in known quantity for both flushing and adding 3-5 gallons to the black tank after flushing.

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  • Wet Bay Mod and Filter Add
    Thanks. Not sure if I have any more pics. The aluminum angle and repainted sheet aluminum was on Amazon.
  • 5th wheel hitch inspection
    Crisis adverted! Glad you found those cracks in time!
  • RV Fresh Water Hose Review – Camco EvoFlex
    I bought this hose about 3 months ago. So far it has worked well. I bought the 50 foot size but wish I went with (2) 25 footers instead as typically 25 would be long enough.
  • Wire gauge rooftop solar to battery compartment
    For all my cable sizing I use a voltage drop calculator. Be less than 3% voltage drop. I size for less than 1% typically. You can use this calculator to see how your added panels will affect your cables efficiency adding panels. You can also pair up your panels in series if you have a charge controller that is designed for those increased voltages. (MPPT) In that case the wire would be just as efficient as what you have even doubling the panels. If possible make the added 2 panels the same as the 2 you already have for total wattage, amperage and voltage.

    As far as a combiner box you can build your own or buy one. I made my own using an ip65 rated box and some din rail.

    https://www.calculator.net/voltage-drop-calculator.html
  • 12 Volt Refrigerators
    Thanks for the info!
  • 12 Volt Refrigerators


    I am interested in hearing more about your switch. We currently have a 12c/f Norcold LP/Electric fridge that we run on electric through our inverter most of the time. It uses a lot of electricity about 450 watts with the heating element on. Much more than a standard residential fridge which I measured at roughly 150 watts. It sounds like your everchill is roughly 70 watts? What size did you remove to replace it? I wonder if it would fit into the same space as our 12c/f Norcold.

    Most days we are fine leaving the fridge on electric but we do need to switch it to gas sometimes and would prefer something more efficient.

    Thanks!
  • Bogart charging LiFePo
    I asked some follow up questions. It's pretty cool that BB takes the time to answer. I'm sure I will learn something.

    BTW I ordered 3 BB 100ah batteries directly from BB to install in an RV that we sold after taking my custom battery out. I have to say that the packaging and general quality of the batteries was excellent.
  • Bogart charging LiFePo
    So, here is the response:

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    In that video from BB they say it is the passive mechanism of the BMS that balances the cells. That is what had me confused. There is no mechanism in a passive BMS to balance cells in series.

    It is also not higher voltage that balances the cells. The cells will all rise at their own rate based on their capacity. The first cell that hits the voltage trigger for the BMS will shut the battery charging off. The remaining cells will just not be completely full. A very small difference anyway if you could balance and fill them all equally/fully.

    A 12v 4 cell LiFePO4 battery is full at 13.6-13.7 with a very small amount left possible after that. I think the reason why companies like Lion and BB chase these higher voltages is the faster charging rate that can occur towards the top end of the charge cycle due to most controllers that stage down the charging rate as the battery voltage approaches the battery full SOC programmed into the charger.

    The narrator in that video is Denis the company CEO. The e-mail response was from an engineer there. I am still not satisfied with their explanations. I was pretty sure that their BMS had nothing to do with balancing as the video mentioned but I am also fairly certain it is not charging voltage either that is miraculously balancing cells in series. There is no way to explain that in my mind.

    But, I am happy to learn if I am wrong. :) I do appreciate that they responded to a fairly technical question.
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  • Bogart charging LiFePo
    It confuses me. As it has been explained to me the passive type BMS used in drop-ins are simply a switch that is activated be individual cell voltages. One the first cell gets to the voltage limit the pack is isolated from charging all together. Passive BMS does not balance. Maybe BB is using an active balancing BMS but those typically are always balancing. Cells don't gain or lose capacity so they need to always be adjusting so they all land together at the top or bottom. The interconnecting cables are typically small and can only carry so much current.

    In any case I was curious enough to ask BB. If they do have some sort of system that top balances but only at high voltages I might be interested in a similar system myself or would at least like to educate myself on how it works.

    So far no response but if they do I will let you know what they say.
  • Bogart charging LiFePo
    I'm not familiar with the trimetric charger but if it is customizable for it's charging voltages it's better to err on the low side with Lithium batteries. LiFePO4 chemistry is almost full at 3.4v/cell or 13.6v for 4 cells in series. Unlike led acid these batteries do not benefit from regular 100% full charging, in fact they will probably enjoy more lifecycles by limiting the voltage range. The maximum charging voltage a LFP cell should see without fear of damage is 3.65 or 14.6volts in a 12v battery. Any more than that and you are relying on the batteries BMS to protect the battery by disconnecting the current from the charger internally in the battery. That is the job of the BMS so all should be fine but the relative gain in battery capacity is almost zero after 14v anyway.

    14v would fill 99+% of a cells capacity.

    My own chargers are set at the equivalent of 13.7v on a 12v battery. IMO there really isn't any good reason to apply more voltage to an LFP battery other than that it will retain a higher charging current towards the tail end of its capacity during the charge cycle. That can be valuable if you are trying to squeeze every bit of solar charging for the last bit of the batteries capacity. That is the only real benefit to these higher charging voltages IMO.




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  • No water heater rod?
    Yes, normal. Atwood uses aluminum for the tank material. No anode rod needed to counter rust.