This charger/converter + this battery = ?

Hi lenr,

That "fame" is 15 minutes every 20 hours. That can be more or less ignored.

lenr wrote:
Don't know if it is true for all AGMs, but Trojan T-105 AGM says do not equalize. I believe that periodic equalization is Progressive Dynamics big claim to fame with the charge wizard. I would choose a converter that allows setting the maximum voltage.

Gdetrailer wrote:


What a complete waste of money on a AGM battery for THIS purpose.

For what YOU are doing a much cheaper group 24 or 27 combo RV/marine LEAD ACID battery WILL do exactly what you need to do AND should be able to squeak out 8-10 yrs of life provided you are able to add water (IE has removable caps).

Been there, done that with my first TT, ran furnace overnight and still had some battery leftover in the morning..

Sometimes we can easily get caught up in modern battery/technology hype and willing to dump tons of money into plain overkill..

Kind of like using a cannon to swat a fly..

It's funny you should mention running the furnace overnight. That's one of the reasons I wanted a 200ah bank. My previous bank was 2 Trojan T-105's. I tend to drift to overkill to be prepared for the odd time I think I'll need that "extra". My stereo system has to too many watts of power, my car goes too fast, and my barbeque grill can cook 20 hamburgers at a time.

lenr wrote:
Don't know if it is true for all AGMs, but Trojan T-105 AGM says do not equalize. I believe that periodic equalization is Progressive Dynamics big claim to fame with the charge wizard. I would choose a converter that allows setting the maximum voltage.

The PD "equalize" is not the same thing as what the AGM advice is warning about. All the PD "equalize" does is give a shot of 14.4 every so often amongst its 13.2 storage "stage" It really should be called "destratification".

In fact you do "equalize" an AGM if needed, except they call it "conditioning" and maybe not to such a high voltage as with Wets. Say 15.5 for an AGM vs 16.2 for a Wet.

It depends, as usual.

RKW wrote:

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.

What a complete waste of money on a AGM battery for THIS purpose.

For what YOU are doing a much cheaper group 24 or 27 combo RV/marine LEAD ACID battery WILL do exactly what you need to do AND should be able to squeak out 8-10 yrs of life provided you are able to add water (IE has removable caps).

Been there, done that with my first TT, ran furnace overnight and still had some battery leftover in the morning..

Sometimes we can easily get caught up in modern battery/technology hype and willing to dump tons of money into plain overkill..

Kind of like using a cannon to swat a fly..

Don't know if it is true for all AGMs, but Trojan T-105 AGM says do not equalize. I believe that periodic equalization is Progressive Dynamics big claim to fame with the charge wizard. I would choose a converter that allows setting the maximum voltage.

Lots of reports of the wizard taking care of batteries to live 10 years or more.
If the 13.6 does not quite do it for you there is a short boost to 14.4 every 20 hours.

MEXICOWANDERER wrote:
BOOST Mode 14.4 Volts – Rapidly brings the RV battery up to 90% of full charge.
NORMAL Mode 13.6 Volts – Stupidly incompletes the charge.

If the charge WIZARD would let the charger CONTINUE to charge at 14.4 then the battery has a chance. If not then the WIZARD is degraded to CHARGE DUNCE, cone hat stool and all.

And please oh please how does the charge dunce KNOW when a battery bank has reached 90 - 95% charged? By ESPN?

Yes the PD blurb on all that seems to assume a 10% charge rate to let it get to 90% before reaching 14.4. It is all quite stupid.

The Charge Wizard changes that for those willing to use it. Now you can keep the voltage at 14.4 as long as you like. If the initial 4 hours is too short, just hit the thing again for another 4 hours.

BOOST Mode 14.4 Volts – Rapidly brings the RV battery up to 90% of full charge.
NORMAL Mode 13.6 Volts – Stupidly incompletes the charge.

If the charge WIZARD would let the charger CONTINUE to charge at 14.4 then the battery has a chance. If not then the WIZARD is degraded to CHARGE DUNCE, cone hat stool and all.

And please oh please how does the charge dunce KNOW when a battery bank has reached 90 - 95% charged? By ESPN?

The review notes that big battery is good for 10 years on standby, as opposed to cycle use, so it should be fine for extended time at 13.6 on FHU.

You must have a reason to want a 200AH battery instead of a 100AH one while on FHU, but that wasn't the question.

time2roll wrote:
I would have Lifeline or lithium but the combo will be fine.
Careful lifting an 8D.

Thanks!