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33 Replies

  • BFL13 wrote:
    Review of the battery here, with more spec info and analysis for RV use etc.

    https://www.deepcyclemarinebattery.com/reviews/mighty-max-ml4d-12v-200ah-4d-sla-agm-battery.html

    The 45 amp charger is rated above the AGM 20% "rule" for bulk stage. Usually in RVs you won't see that 45 at the battery but might get 40 or so.

    You would need to use the CW to keep it at 14.4 for the whole time until the battery gets down to 1 amp (signal it is full) before dropping to 13.6. And you will need an ammeter to know when it is down to that 1 amp. (I use my Trimetric for that with my AGMs)

    The 14.4v of the PD is at the low end of the charging voltage range in the spec, which is at 77F. Any cooler out than 77F makes the 14.4 too low, but also that temp is related to battery temp while being charged, so it should be ok down to some lesser ambient.

    So it could be ok as a combo. The one 200AH is not well suited for high amp short time inverter work (as with a MW or toaster), as mentioned in that linked review above.


    Thanks for the in depth reponse.

    Everyone who asks a question is hoping for a particular answer and I was hoping that I could pair the two and forget them, out of sight and out of mind. Sounds like I'll have to find my Trimeteric and return it to service.

    The suitability of the battery vis a vis the inverter isn't an issue as I've never utilized an inverter.

    FYI to the forum, 90% of the time my RV will be sitting on the pad and connected to shore power and in 20 years of RVing I've probably only boondocked 10 times and all those were just overnight.
  • I would have Lifeline or lithium but the combo will be fine.
    Careful lifting an 8D.
  • Review of the battery here, with more spec info and analysis for RV use etc.

    https://www.deepcyclemarinebattery.com/reviews/mighty-max-ml4d-12v-200ah-4d-sla-agm-battery.html

    The 45 amp charger is rated above the AGM 20% "rule" for bulk stage. Usually in RVs you won't see that 45 at the battery but might get 40 or so.

    You would need to use the CW to keep it at 14.4 for the whole time until the battery gets down to 1 amp (signal it is full) before dropping to 13.6. And you will need an ammeter to know when it is down to that 1 amp. (I use my Trimetric for that with my AGMs)

    The 14.4v of the PD is at the low end of the charging voltage range in the spec, which is at 77F. Any cooler out than 77F makes the 14.4 too low, but also that temp is related to battery temp while being charged, so it should be ok down to some lesser ambient.

    So it could be ok as a combo. The one 200AH is not well suited for high amp short time inverter work (as with a MW or toaster), as mentioned in that linked review above.

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