What Can I Expect

[Rockwood27]

Originally Posted by Doctor Old

Unfortunately, I don’t have a 30 amp nor an adapter.

You can buy a 30 to 15 amp adapter at almost any Walmart, Tractor Supply or hardware store.

[Rockwood27]

Originally Posted by Doctor Old

Well, that would suck. The rig is not that old. 2019 model. That’s not an expense I’m ready to swallow after just getting it.

Was this a new, old stock unit or used? Dealers don't always take the best care of batteries.

To prolong battery life, try to keep them above 50% state of charge (i.e. approximately 12.2 volts).

[Doctor Old]

Originally Posted by Rockwood27

Was this a new, old stock unit or used? Dealers don't always take the best care of batteries.

To prolong battery life, try to keep them above 50% state of charge (i.e. approximately 12.2 volts).

It’s pre-owned. 20,000 miles. Battery level has stayed pretty high until today. Of course I don’t check it everyday. Just happened to notice it.

[themexicandoctor]

Originally Posted by Doctor Old

Well, that would suck. The rig is not that old. 2019 model. That’s not an expense I’m ready to swallow after just getting it.

Read that pdf, first.

Once you have digested this information you will have a better understanding of what is happening.

And refrain from making statements about expenses you are not ready to swallow yet.

There is always reasons why previous owners are so very joyous after you give them cash, turn the key & wave goodbye.

If you left a Hidden Camera you would see them suddenly become 10 years younger, high fiving each other & hugs all around, especially if this is their first rig.

And then you see members like Booster in a 2007 Rig who are completely squared away & will be for another 10 years.

You are now The Owner.

These things don't fix themselves.

And the things that power your rv experiences, need juice, good juice.

With a lot of research & luck, there are ways to minimize the costs of your RV learning curve, and, an honest RV Workshop.

What is the brand & model # of the batteries in question?

The best thing you can do now, is find somewhere you can be connected for 24 - 48 hours to shore power.

Even better, if the batteries don't read FULL after 24-36 hours & by studying that material & all the similar threads here, you might by then feel confident enough to "equalize your batteries ..."

Search amongst all threads here, understanding Battery Dynamics is critical to having the Peace of Mind to enjoy your Rig.

If most of the time you are driving more than two hours per day, it should be sufficient & of course, access to the solar.

BUT THE BATTERIES HAVE TO BE IN EXCELLENT CONDITION TO BEGIN WITH ALONG WITH YOUR CHARGING SYSTEMS.

Your enemy is called Sulfation.

Understand this process & you are well on the way to happier ownership.

I personally believe a 200 watt solar system in a Class C isn't large enough to manage your daily demands unless its a very small fridge & you are shore camping.

Shore hook ups give you so much wiggle room even if its only every 2-3 days.

Solar is an add on, its not the total answer unless you invest $5-10k or more on a Class C & you vacation where there is plenty of sunlight.

What fridge model & manufacturer do you have?

Did you say whether or not you have an Inverter Charger?

[SteveJ]

Originally Posted by Doctor Old

It’s pre-owned. 20,000 miles. Battery level has stayed pretty high until today. Of course I don’t check it everyday. Just happened to notice it.

Battery University is an excellent web site to go to for info on all things battery and charging systems.

Happy reading.

[themexicandoctor]

Originally Posted by SteveJ

Battery University is an excellent web site to go to for info on all things battery and charging systems.

Happy reading.

Thank you Steve - I too will avail myself of this resource.

By the way Doc, there is a lot of misinformation out there.

And sometimes on here.

But here at least, the obvious is shot down very quickly via spirited debate.

[JohnnyCLE]

If I read one of your comments right, you mentioned your Go Power inverter is always on? On my unit the battery disconnect only disconnects the 12v loads. Your solar should charge without the "Battery Connect" switch on. If the inverter is on it may be pulling perhaps 100w per hour of 110v current out of your batteries.

When parked make sure your inverter is off and the 12v loads are disconnected.

[mumkin]

Originally Posted by markopolo

...Fully charged AGM batteries will have a resting voltage of approx 12.8V.

Why is your chart different from all the other charts that I have seen on battery charge levels for AGMs. I have about a half dozen of them by now and each of them gives 12.0 or 12.1 for 50%. (12.6 as 100%, 12.3 as 70% and 11.8 as 30%)

This is the first chart that I have ever seen that declares that 12.0 is 25%??? Is it some sort of new testing system?

Very confusing... I don't have it, but the RT voltstart is set to come on when the battery hits 11.8.

[booster]

Originally Posted by mumkin

Why is your chart different from all the other charts that I have seen on battery charge levels for AGMs. I have about a half dozen of them by now and each of them gives 12.0 or 12.1 for 50%. (12.6 as 100%, 12.3 as 70% and 11.8 as 30%)

This is the first chart that I have ever seen that declares that 12.0 is 25%??? Is it some sort of new testing system?

Very confusing... I don't have it, but the RT voltstart is set to come on when the battery hits 11.8.

The chart is confusing in that it says it is a "fixed load test" but then list "open circuit" voltage.


My suspicion would be that this would be the voltage seen during a fixed load test, immediately after the test was completed before the battery had rested and rocovered voltage.

[Bud]

Originally Posted by booster

The chart is confusing in that it says it is a "fixed load test" but then list "open circuit" voltage.


My suspicion would be that this would be the voltage seen during a fixed load test, immediately after the test was completed before the battery had rested and rocovered voltage.

And if I understand, the fixed load data is not there, so not very useful. I mean when I use my voltage meter, I need to know what is use - one led bull or the furnace and tv in order to interpret what I'm seeing.

[markopolo]

The chart or very similar charts are in various guides and technical manuals. Here's another from Interstate (I think):



I think they are very useful for RV'ers because they will help you keep the batteries above 12V.

Maybe think of the charts as being effective remaining capacity instead of technical remaining capacity.

Effectively you have little capacity left once below 12V. Technically, I consider 11.6V to be 20% SOC.

Voltstart's 11.8V set-point is compromise because it is completely unaware of the systems actual State of Charge. Voltage varies depending on the load in addition to remaining capacity.

[Bud]

Originally Posted by markopolo

The chart or very similar charts are in various guides and technical manuals. Here's another from Interstate (I think):



I think they are very useful for RV'ers because they will help you keep the batteries above 12V.

Maybe think of the charts as being effective remaining capacity instead of technical remaining capacity.

Effectively you have little capacity left once below 12V. Technically, I consider 11.6V to be 20% SOC.

Voltstart's 11.8V set-point is compromise because it is completely unaware of the systems actual State of Charge. Voltage varies depending on the load in addition to remaining capacity.

The numbers are agm?

[Doctor Old]

Originally Posted by themexicandoctor

Read that pdf, first.

Once you have digested this information you will have a better understanding of what is happening.

And refrain from making statements about expenses you are not ready to swallow yet.

What is the brand & model # of the batteries in question?

What fridge model & manufacturer do you have?

Did you say whether or not you have an Inverter Charger?

The batteries are Duracell Ultra Deep Cycle BCI Group 31M 105AH SLI31MDC
The fridge is a Nova Kool 6100 Compressor
Using Converter, no inverter

Thanks for all your help. I have been reading and educating myself this a.m. More to learn yet. I did find an adapter and have plugged the rig in. What was surprising was after driving around this morning the one meter read that the battery was full but the Go Power was at about 75% and at 12.7 on the digital. We’ll see what happens

[markopolo]

Temperature affects voltage as well so the charts are very basic guides.

I think Doctor Old's monitor panel looks like this:
convenience center.jpg

The voltages are below the lights: low, 11.2, 11.7 & 12.3 so will show full with the batteries actually around 50% or so.

[Doctor Old]

@Markopolo Exactly and this is what my Go Power currently looks like:
3D98F5F0-9510-4DBA-9467-B1B31323C595.jpeg

[Doctor Old]

Originally Posted by booster

That battery is an AGM and is listed as a combo battery. I would expect the voltages to be higher than in the posted chart, but we all know that there are lots of variations between batteries of different mfgs, age, size, etc.

Coachmen lists this as a “Flooded” battery

[markopolo]

Marine / RV flooded battery (wet cell) - https://www.batteriesplus.com/batter...le/12/sli31mdc

[booster]

Originally Posted by markopolo

Marine / RV flooded battery (wet cell) - https://www.batteriesplus.com/batter...le/12/sli31mdc

Yep, somehow my search brought up a very similar AGM style, reference deleted.


https://www.batteriesplus.com/produc.../sli31dtmagmdc

[themexicandoctor]

As I stated at the beginning, you are in the right place Doc.

Even Booster who I believe would take the Space Shuttle down to its last screw to rebuild it for another 2% increase in performance had his own learning curve.

The fact they are coming back, is a good thing.

And you always have the option of putting them through a Equalisation Cycle.

Unlike a Dead Horse, Batteries, especially high quality* AGM's can be resurrected from the dead.

*I don't know if your batteries are of reasonaable quality, U only trust Lifeline.

What is your relationship with the previous owner or was it non-existent because you purchased from a dealer?

Knowing what the previous owner did can be of value, especially if you discover he knew nothing about battery chemistry.

[themexicandoctor]

I just clicked on the link - not a good battery at all but perfect for a newbie, think of them as bottom of the barrel learning wheels.

Once you get a Black Belt in Battery Chemistry, contact Andrew Finkelstein at the Lifeline Factory in San Dimas, CA.