group 31 battery

[rox]

Hi Guys, I am lost in the world of what battery is right for my rig. I am in the middle of a complete reno on our oldie and will now be running all LED lights, a new water pump and minimal other power items. I want to be able to dry camp for at least 5 days. I was told by the dealer at the RV store that an Interstate group 24 12V battery would be sufficent with the LED lights and the fact there is no furnace. I then went to a store that specializes in batteries and they recommended/sold me a Crown group 31 battery (specs below). Now that I am home I am reading mixed reviews on this set up as some say it is not a "true" deep cell?

I would love any feedback before I grind off the current mounting bracket on my frame and have a new larger one welded on. I did consider 2 6volts, but I was concerned about the size and extra weight, but would make the plunge if this group 31 wont cut it.

thank you all eggers,
Rox

[rox]

Sorry, lets try that again. The one I bought is the last one on the list.

thanks

[Ed Harris]

I don't think there is anything in the specs you listed that can give us a clue about the suitability of this battery on your rig?
The actual construction of the battery is what determines its label as a Deep Cycle model or not and I have no idea about that other than it seems to be labeled as DC as opposed to DP on that chart.

The construction and design of the internal components is the difference as the true deep cycle battery will have thicker more rugged plated inside capable of deep discharge with less negative effect.

Of course the larger the group rating the more current output and run time regardless and using two 6 volt models just makes a bigger whole unit. So the bigger it is the longer it should run regardless of the construction and then the deep cycle models should be usable even longer than the starting or DP models.

Just not enough info to help?

[rox]

Originally Posted by Ed Harris

I don't think there is anything in the specs you listed that can give us a clue about the suitability of this battery on your rig?
The actual construction of the battery is what determines its label as a Deep Cycle model or not and I have no idea about that other than it seems to be labeled as DC as opposed to DP on that chart.

The construction and design of the internal components is the difference as the true deep cycle battery will have thicker more rugged plated inside capable of deep discharge with less negative effect.

Of course the larger the group rating the more current output and run time regardless and using two 6 volt models just makes a bigger whole unit. So the bigger it is the longer it should run regardless of the construction and then the deep cycle models should be usable even longer than the starting or DP models.

Just not enough info to help?

I presume the lable above the chart that states marine would indicate it is not a true deep cell. I went to a store that only sells batteries trusting this is what they specialize in, but I think I made a mistake. As much as I would like to I can't imagine fitting two 6v on my little frame.

[Ed Harris]

I would not count too much on your presumption.

Labeling as Marine does not preclude them being a Deep Cycle model at all?
In fact if you look at the chart and the battery designations it seems obvious to me that there are DP(Dual Purpose) and DC(Deep Cycle) batteries listed and the last one you are looking at is then listed as a Deep Cycle.

Unless of course this is not what the designations really mean?

Marine labeling would sort of imply more rugged construction than non-marine to me.

[Bill K]

That battery is a true deep cycle and is built with heavier plates.

Bill K

[rox]

Originally Posted by Ed Harris

I would not count too much on your presumption.

Labeling as Marine does not preclude them being a Deep Cycle model at all?
In fact if you look at the chart and the battery designations it seems obvious to me that there are DP(Dual Purpose) and DC(Deep Cycle) batteries listed and the last one you are looking at is then listed as a Deep Cycle.

Unless of course this is not what the designations really mean?

Marine labeling would sort of imply more rugged construction than non-marine to me.

I may be wrong but everything I have ready has said that a battery is not a true deep cycle when it has the title marine, it is a hybrid with spoung lead rather then solid plates. Still I am sure it will do the job either way, thanks.

[rox]

Originally Posted by Bill K

That battery is a true deep cycle and is built with heavier plates.

Bill K

Thank you Bill, this helps. Will this battery is adequate for 5+ days of dry camping with my set up of powering all LED lights, pump and few other devices without running the battery down too far before a good charge? I am looking for info as we will be on the road for 3 weeks soon and need this min. I have to change the frame mounts so I rather not do so until I am confident this will do the job, if not I will have to add the extra weight and size of two 6V. I am guessing I will draw as little as 10 amps a day, this adds up to more then 5 days, but I would love first hand experience as I don't have any.

[Bill K]

I can not answer your question as I use my trailer as a place to sleep while traveling and don't stay put more than a day or two.

Bill K

Originally Posted by rox

Thank you Bill, this helps. Will this battery is adequate for 5+ days of dry camping with my set up of powering all LED lights, pump and few other devices without running the battery down too far before a good charge? I am looking for info as we will be on the road for 3 weeks soon and need this min. I have to change the frame mounts so I rather not do so until I am confident this will do the job, if not I will have to add the extra weight and size of two 6V. I am guessing I will draw as little as 10 amps a day, this adds up to more then 5 days, but I would love first hand experience as I don't have any.

[Ed Harris]

OK
I went to the Crown website and if you poke around a little it is clear that they make several lines of batteries and the model you bought is from the Marine line not the Deep Cycle line.
It is a Deep Cycle model in the Marine line but maybe not the most focused designed for that specific application,it is sort of difficult to really see the differences in real world terms.

I know I got a Trojan Deep Cycle GR 31 and crammed it into my Casita but I have not really tried to see what the endurance is based on your trip requirements.

Each setup is different and all I can suggest is to take a Voltmeter of some kind and watch the Voltage drop as you use the battery.
You also have the option of getting a second matching battery if the 1 is not enough and you will be getting them close enough together in time that they would likely be OK together in Parallel.

Otherwise the Golf Cart volters will certainly give you more current and runtime too if starting from scratch.

If you already have one though just charge it and go see what it does! You can also get a small,cheapish Solar system like the Harbor Freight model which will likely keep you topped off if used to charged during the day.

[Bill K]

Ed,
The 31DC130 battery is NOT listed as a marine battery, it is listed as a Deep Cycle battery.

By marine I mean Duel Purpose.

Bill K

Originally Posted by Ed Harris

OK
I went to the Crown website and if you poke around a little it is clear that they make several lines of batteries and the model you bought is from the Marine line not the Deep Cycle line.
It is a Deep Cycle model in the Marine line but maybe not the most focused designed for that specific application,it is sort of difficult to really see the differences in real world terms.

I know I got a Trojan Deep Cycle GR 31 and crammed it into my Casita but I have not really tried to see what the endurance is based on your trip requirements.

Each setup is different and all I can suggest is to take a Voltmeter of some kind and watch the Voltage drop as you use the battery.
You also have the option of getting a second matching battery if the 1 is not enough and you will be getting them close enough together in time that they would likely be OK together in Parallel.

Otherwise the Golf Cart volters will certainly give you more current and runtime too if starting from scratch.

If you already have one though just charge it and go see what it does! You can also get a small,cheapish Solar system like the Harbor Freight model which will likely keep you topped off if used to charged during the day.

[cpaharley2008]

If you go to The 12volt Side of Life (Part 1), you should be able to determine your needs. A 110 a/h battery is only good for 44 a/h before recharging. You want to go 5 days or 9 a/h per day. I do not think you will make it. With refer/alarms/pump/fan/led lights, you will probably need about double that. I'd guessimate 2.5 days. Without solar or recharging that would be my estimate.

[Ed Harris]

Actually that Battery model number is listed in BOTH the Marine and Deep Cycle charts?

[honda03842]

Originally Posted by Ed Harris

Actually that Battery model number is listed in BOTH the Marine and Deep Cycle charts?

Batteries are nice but need support systems to be truly useful. For me that amounts to a small but reasonable solar panel or direct charging from the tow vehicle while driving.

We have used both approaches sometimes in the same day. We had two 60 watt panels. In addition we had the ability to charge directly from our tow vehicle. We installed a switch on our dash that allows to charge the trailers battery when we're moving. This allowed us to have a traditional AC Fridge run off an inverter and never worry about it discharging our battery.

An appropriate solar panel is a lot less than most generators and direct charging from your car while the engine is running is virtually free.

Before we leave for our loop of the USA we hope to add a Solar Panel.

Norm

[rox]

Yes, the battery will be able to charge off the tug and when we have shore power, but I want to figure out how long I have when dry camping. Solar maybe something in the future, but for now I have put way too much money in this trailer to spend any more. thanks for your suggestions.

Originally Posted by honda03842

Batteries are nice but need support systems to be truly useful. For me that amounts to a small but reasonable solar panel or direct charging from the tow vehicle while driving.

We have used both approaches sometimes in the same day. We had two 60 watt panels. In addition we had the ability to charge directly from our tow vehicle. We installed a switch on our dash that allows to charge the trailers battery when we're moving. This allowed us to have a traditional AC Fridge run off an inverter and never worry about it discharging our battery.

An appropriate solar panel is a lot less than most generators and direct charging from your car while the engine is running is virtually free.

Before we leave for our loop of the USA we hope to add a Solar Panel.

Norm

[honda03842]

We did the following test when we added a dorm fridge to see how long we could run off the battery. It should provide you with a good first order answer.

Plug your rig in and fully charge your battery (about 12.65 volts). You need to run the converter to charge it. To find out if it's fully charged you need to shutoff the converter (un-plug the rig) and wait a few minutes to let the battery normalize and then measure it.)

To run the test unplug the trailer and turn the number of LEDs you would typically use and what ever else you use. To test for the water pump load, run the water for the number of minutes you might in a day. (Actually the number of minutes a pump runs in a day is not many) and check the battery voltage every now and than.

When the battery voltage drops to 11.6 it is considered discharged. (I am not sure that it's 11.6 but it's certainly at a state that you would no longer want to discharge it.)

Doing this for a couple of days will tell you how long you have. You should be able to test for two days in one by leaving the lights on for 24 hours.

Norm

[rox]

Originally Posted by honda03842

We did the following test when we added a dorm fridge to see how long we could run off the battery. It should provide you with a good first order answer.

Plug your rig in and fully charge your battery (about 12.65 volts). You need to run the converter to charge it. To find out if it's fully charged you need to shutoff the converter (un-plug the rig) and wait a few minutes to let the battery normalize and then measure it.)

To run the test unplug the trailer and turn the number of LEDs you would typically use and what ever else you use. To test for the water pump load, run the water for the number of minutes you might in a day. (Actually the number of minutes a pump runs in a day is not many) and check the battery voltage every now and than.

When the battery voltage drops to 11.6 it is considered discharged. (I am not sure that it's 11.6 but it's certainly at a state that you would no longer want to discharge it.)

Doing this for a couple of days will tell you how long you have. You should be able to test for two days in one by leaving the lights on for 24 hours.

Norm

Thanks Norm, I guess I should had been more clear. The battery is brand new, if I don't use it I can exchange it for 6volts (or what ever I choose). I was trying to get feedback from those who have used group 31's with similar set up (LED's) for 5+ days before I hack my trailers frame and plug in the new battery making it un-returnable if it wasn't enough power. I am really thinking of going the two 6 volt route though, if I can make it fit on my frame more power would be better then not enough.

Funny though, guy at the RV store swore up and down a bottom line group 24 would get me at least 5 days since I switched to all LED's I really don't think the stronger group 31 will make it 5 days and so 6v I will likely go.

[cpaharley2008]

here is a spreadsheet if you want to do it on paper first
RV Electrical Power for Dry Camping

[rox]

Originally Posted by cpaharley2008

here is a spreadsheet if you want to do it on paper first
RV Electrical Power for Dry Camping

Thank you, this is really helpful. I had no idea you multiply AC items by 10 when running on DC, this may change things up a bit. Now I will build a spreadsheet of my trip.

[Raz]

Hi Rox, We have a group 24 AGM battery rated at 80 AHr. I bought it to do exactly what you want to do, stay somewhere without hook ups for a few days. We run LED's, a water pump, and a small fan modified to use between 200 and 500 mA. of current. With a small solar panel (42 watt) we can stay forever. The longest we have stayed without the panel is 3 days with plenty of battery life left. I'm sure we could go at least 4 and most likely longer. I figure we use less than 5 AHr per day. If it runs out we can live with flashlights for a night. As funds are an issue, I would buy the group 24 and see how you do. Realize that you will be buying a new one in about 3 years, maybe less. When I was at that point I went with the AGM. Raz