Last year I had to replace my 4 12 volt batteries in my fifth wheel on an emergency basis. I had someone staying in it, and one of my old batteries shorted and brought the whole bank down. I had been planning on replacing my six year old set with some AGMs, but when the battery shorted I didn't have time to search for an adequate AGM substitute. Anyway I just went back with what had served me for six years. Well, now I'm adding solar to my RV and have a new Morningstar 60 amp MPPT controller that allows me to custom set the charging parameters. But I cannot find any specific specs on the battery. I can use the presets on the controller for flooded lead acid batteries (there's actually two different ones--one that absorbs at 14.6 and another that does so at 14.7--but having the capability to custom set the parameter is too much to resist. Does anyone have any idea what I should set on the controller for these batteries? They are Sam's Club Energizer E29HM Marine/RV Deep Cycle.

I would pick "flooded." It doesn't matter much whether you pick 14.6 or 14.7What matters is how long it stays at 14.6 or 14.7 after it gets the batts there. You want it to stay that high till they are charged up, then drop to "float" at 13.6ish. If you get to 14.6ish real early in the day, you might want to drop to float before dark if you start losing water from staying at 14.6ish too long each day. If the charging profile is to drop to float after two hours of absorption that might be too soon. You can fiddle with all this by setting your float voltage to be the same as absorption voltage and then let darkness happen to be your float time.It varies for all that by just how much daytime is left once you get them to 14.6ish, and that varies all year by latitude and time of year.So it is best to have adjustable everything and keep an eye on things and adjust as required. Solar is NOT a "set and forget" kind of situation.

It is hard sometimes to find the actual specs for any given battery...What I do is always compare the battery size and weight to a TROJAN BATTERY SPEC listing and it will come up pretty close to the spec you are wanting to know about...Look down the list for a 12V Battery Group 29 battery in the case...This is the link for TROJAN Battery Specification Guide..TROJAN PRODUCT SPECIFICATION GUIDEWorks good for my different sources of batteries...ADDED NOTE: Well it appears in this case TROJAN does not have a GROUP 29 12VDC Battery listed haha... Disregard I reckon...Roy Ken

So might it be best to just use the default flooded 14.7 profile and watch how the batteries actually perform with the solar charger, then custom adjust? I can't find any specs on the net for these batteries. The Morningstar default is three hours absorption.

howardwheeler wrote:So might it be best to just use the default flooded 14.7 profile and watch how the batteries actually perform with the solar charger, then custom adjust? I can't find any specs on the net for these batteries. The Morningstar default is three hours absorption.That's what I would do for sure. That is likely a good profile as is, in most conditions. If you are "overcharging" each day this will show up in water loss. "Undercharging" will show up as low SG by hydrometer readings taken every so often.

Charging specs for group 29HM Deep Cycle Marine/RV battery

BFL13
Explorer II
Mar 26, 2017
howardwheeler wrote:
So might it be best to just use the default flooded 14.7 profile and watch how the batteries actually perform with the solar charger, then custom adjust? I can't find any specs on the net for these batteries. The Morningstar default is three hours absorption.

That's what I would do for sure. That is likely a good profile as is, in most conditions. If you are "overcharging" each day this will show up in water loss. "Undercharging" will show up as low SG by hydrometer readings taken every so often.
howardwheeler
Explorer
Mar 26, 2017
So might it be best to just use the default flooded 14.7 profile and watch how the batteries actually perform with the solar charger, then custom adjust? I can't find any specs on the net for these batteries. The Morningstar default is three hours absorption.
RoyB
Explorer II
Mar 26, 2017
It is hard sometimes to find the actual specs for any given battery...

What I do is always compare the battery size and weight to a TROJAN BATTERY SPEC listing and it will come up pretty close to the spec you are wanting to know about...

Look down the list for a 12V Battery Group 29 battery in the case...

This is the link for TROJAN Battery Specification Guide..

TROJAN PRODUCT SPECIFICATION GUIDE

Works good for my different sources of batteries...

ADDED NOTE: Well it appears in this case TROJAN does not have a GROUP 29 12VDC Battery listed haha... Disregard I reckon...

Roy Ken
BFL13
Explorer II
Mar 26, 2017
I would pick "flooded." It doesn't matter much whether you pick 14.6 or 14.7

What matters is how long it stays at 14.6 or 14.7 after it gets the batts there. You want it to stay that high till they are charged up, then drop to "float" at 13.6ish.

If you get to 14.6ish real early in the day, you might want to drop to float before dark if you start losing water from staying at 14.6ish too long each day.

If the charging profile is to drop to float after two hours of absorption that might be too soon. You can fiddle with all this by setting your float voltage to be the same as absorption voltage and then let darkness happen to be your float time.

It varies for all that by just how much daytime is left once you get them to 14.6ish, and that varies all year by latitude and time of year.

So it is best to have adjustable everything and keep an eye on things and adjust as required. Solar is NOT a "set and forget" kind of situation.

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Charging specs for group 29HM Deep Cycle Marine/RV battery

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