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Recommendations for Best RV Voltage Converter Battery Charger AND 6VDC Batteries

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Wiredawg

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Friends,

The voltage converter in my 2015 Mobile Suites has fried second set of batteries and looking for the best replacement that has smart charger feature. RV was in shop for twelve weeks, mostly due to me not being able to pick it up from surgery, and batteries were mostly dead. Got it home and added more than a pint each of distilled water to top them off. Three weeks later, the batteries completely dead (0 VDC) with RV unplugged. When plugged in, OEM converter shows 13.6VDC on power control center battery voltage meter.

We store RV in my 60ft X 60 Ft shop and keep it plugged into shore power all the time. A friend recommended using the battery cutoff switch, but not sure if that cuts off charging the batteries. Not sure I want that either.
Any recommendation for 6VDC Batteries?

Thanks, Ron
 
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I have had great luck with Deka batteries and use them in a 12v configuration on my trailer as I cannot fit 6v, my local battery shop suggested plugging in the trailer to shore power for a week then unplug for a week to keep them from overcharging.

Unfortunately my trailer is stored outdoors and once I added solar I do not plug the trailer in.
 
I use Lifeline batteries and Progressive Dynamics converters.

Even then I don’t leave the batteries hooked up after 2-3 days of plugged in. I just turn the battery switch off and use the converter for DC power until 2-3 days before camping again.

Leaving batteries plugged into a charger is a common way to kill them, especially with cheap converters.
 
Kill switch here. I went through a couple 12 volt RV batteries before I figured out that extended time on 120 volt shore power was the culprit.

You can upgrade to a fancier charger / inverter unit or simply add a constant duty solenoid and switch to isolate the battery (ies)......
 
I too disconnect the batteries, via a switch, when the trailer isn't in use. I have no reason to keep it powered up.

As for keeping it hooked up and using the cutoff switches, yes it will prevent the batteries from getting a charge. But, there is always a but, it is my understanding that the batteries act as a sort of buffer that protects the 12 volt system if there is a surge in voltage, like when you move the slides in and out.
 
I second the Deka brand. We run Cushman industrial carts in our plant to get around (think oil refinery plant size wise). Both 6 and 8 volt batts, depending on the rig. they get run pretty much round the clock 7 days a week and don't get plugged in like they should. We just replaced a set that was 8 years old but only one of them had actually. failed. That's pretty dang good considering the usage and lack of maintenance they get. They aren't cheap but I got tired of all the premature failures I have gotten out of Interstate Batteries over the last several years so I'm back to running Deka in my vehicles as well.

I just scored a killer deal from the vendor we use, these guys were bought right at a year ago for a customer. 6 months later the customer traded the cart in on a new one because the frame was rotten. All usable parts got pulled and the buggy got scrapped, these batteries have been sitting on Ken's shelf for the last several months. I happen to know the owner of Kenray and by sheer happenstance ran into him at dinner one night, a few beers and $100 later and I've got myself 6 like new 6 volt 75 amp hr batts.
I'm going to buy a solar panel and charge controller and run my outdoor wood burner off of them so I don't have to worry about dragging my little generator out when the power goes TU. I figure 4 will be more than enough for the minimal voltage required for the induction fan and blower, the other two will go in the camper.

IMG_20190723_164208372.jpg
 
I too disconnect the batteries, via a switch, when the trailer isn't in use. I have no reason to keep it powered up.

As for keeping it hooked up and using the cutoff switches, yes it will prevent the batteries from getting a charge. But, there is always a but, it is my understanding that the batteries act as a sort of buffer that protects the 12 volt system if there is a surge in voltage, like when you move the slides in and out.

Yes, I did not mention that I turn the battery switch on before operating landing legs or the slide..
And also make sure it is on before towing as the emergency brake / lanyard thingy needs power to apply the brakes in the event of a trailer disconnect..
 
Friends,

Thanks for all the great inputs. Got news yesterday from Dr. 8 more weeks without full weight on my ankle (sad story) so decided to read ALL the paperwork in my DRV satchel about ALL my power equipment on board. I got educated on what is on my unit. BTW, after replacing the 9Volt battery on my digital multi-meter, I read 3.6VDC on the two 6VDC batteries in series. I found receipt for the batteries purchased in 2017, Auto Craft from Advance Auto Parts.

I read info on my Magnum Inverter/Charger that has optimized (smart) battery charging AND my RV also has Progressive Dynamics Intelli-Power 9200 power converter. So, sounds like both the Inverter/Charger AND the Converter/Charger are connected to the batteries, but think only the Converter/Charger ACTTUALLY charges them.

So, before I go out and buy new batteries, I'm going to test BOTH the Inverter AND the Converter. May take a while as it's tough doing ALL this work on crutches AND only able to put 50Lbs on my left foot (no more ankle)

Again, thanks y'all...

Ron
 
You have good electronics. I can’t say I’d expect to get quality batteries at auto zone, so they probably didn’t like always living above 13V.

For wet cell batteries you cannot beat Costco, otherwise there are some great recommendations in here. My 300AH Lifeline 6V’s are 5 years old and work like new. My last set of them were 10 years old and only replaced due to age.

I would research where your battery switch is inline, should be pre-converter, and shut it off after 48-72 hours of charging post use. PD converters are designed to operate without a battery connected.
 
It's possible your top of the line RV already has a kill switch built in. Also you may have a breaker popped between the batteries and PD charger. Some of the RV fire, CO, and propane alarms are a constant drain. Check if they go off with a factory kill switch.

"Best" for what? How do you intend to use the batteries? Dry camping? RV parks with shore power? Adding water to batteries on shore power is an advantage. They make easy water fill kits help with that task. Budget is always a question because best can leave 6v behind with lightweight LiFePo.

Note the AGM batteries should hold a charge when disconnected via the kill switch for a year. Flooded batteries need a charge about every 30 days just from self discharge.

Lots of 6v discussion here, LiFePo for some cutting edge examples, and and example of measure twice and make selected batteries fit via mods anyway:

https://www.turbodieselregister.com/threads/rv-house-batteries-for-dry-camping.259757/
 
The GOOD controllers like the Progressive Dynamics Intelli-Power line have a charge profile. When it first sees power (120V) it will go into bulk charge or boost charge for a specific time, then to Normal mode which monitors voltage, then Float charge which will hold the battery at the full charge voltage (it does not boil the battery). In theory you can leave a rig plugged in without harm to the battery. If you unplug it, the cycle above repeats when plugged in. With a solar charger the cycle repeats every sun rise. Solar chargers have the additional Equalize charge cycle. That is used to de-sulfate the batteries to extent the useful life of the battery (to a point).

You can see these changes with your DVM to see if it's working correctly. Right after plugging in you should see 14+ volts and then after a couple hours it will drop into the mid to upper 13 volt range and finally just a little lower float voltage. A request for information to the manufacturer of the charger SHOULD get you the information.
 
The PD’s won’t aways go into boost, as it depends on the battery voltage at the time of 120V being applied.

Many of the PD models have, or can have, a charge wizard button that will force boost mode. I use this all the time camping as normally it won’t automatically go into boost but I want boot voltage for a faster charge on the generator.
 
I have had the progressive and charge wizard for a very long time. The RV stays plugged in (for the last 17 years anyway) and I check the level in the batteries monthly (no real usage for about 3 Months) and never had a battery boil out or run dry.
 
I have had the progressive and charge wizard for a very long time. The RV stays plugged in (for the last 17 years anyway) and I check the level in the batteries monthly (no real usage for about 3 Months) and never had a battery boil out or run dry.

How often do you have to add fluid? Or are you not having to add any ever?
 
Friends,
Troubleshooting the dead batteries and facts I have so far with rv plugged into shore power
1. Converter is reading 13.6VDC when pressing battery button on tank level monitor.
2. At batteries, reading 3.6VDC.
3. Auto resetting fuse, reads 3.6VDC on both sides, indicating good.
4. Magnum Display briefly flashes all battery charge LEDs, then goes blank. No LEDs lit.
5. Magnum Inverter/Charger power LED not lit and depressing power button does not light it.

This is all I had Insight to test with shore power plugged in.

With shore power disconnected, the following is observed:
1. Zero displays lit at power management system and battery/tank levels.
2. Batteries still read 3.6VDC.

All power breakers, fuses, and auto resetting relays appear to be good. Only fact I'm not sure of: 120VDC protection to the inverter.

Anyway, I have my Smart Phone with me as I disconnect batteries from RV and check specific gravity of acid in them AND f good reading, place on separate charger to see if they will charge.

EDIT: I have central fill and had added distilled water water two months before breaking prosthetic ankle plus 3 months at dealer, plugged in part of time there, so 5 months when I got rv back and found lead plates exposed, added about a quart of distilled water to them and appeared to work. Since they are down so much, I'm going to disconnect them, plug rv back into shore power, and carefully check if I see 12VDC charging voltage present.

Interestingly, the smart converter is 30 apps, which leads me to believe the Inverter/ charger is responsible for charging batteries. Prior to batteries dead, battery charger LEDs were lit at Magnum remote indicating whichever charging status is occurring.

Thanks for the input and help.

Cheers, Ron
 
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Friends,
I removed batteries and water level is good. I performed specific gravity tests on all cells and they all had the lowest reading on the tester. I currently (lol battery humor) have the batteries out of the RV, connected in series, and charging 12VDC. Stopping further testing today as I've used up my energy and limited mobility. Will resume tomorrow by removing charger, check no-load battery voltage, and test specific gravity of all cells again and report that here.

One thing I confess to is that I need to check water monthly. I had been accomplishing approximately ever 2 months, but missed that maintenance cycle at 2 months due to my injury and subsequent surgery AND the entire
3 months when RV was at dealer. I believe the fact that 5 months went by without battery maintenance is primary cause of my current battery issues.

My lack of understanding AND interpretation of how the RVs systems act when batteries are depleted has me at a disadvantage here. For example, the Lippert auto leveling system does not function with the batteries depleted even while plugged into shore power. Also, Inverter/Charger does not display power on LED when connected to shore power as stated above. Will spend rest of day researching how Inveryer/Charger acts with batteries dead or showing 3.6VDC. It would make sense if a cell(s) were shorted that a current protection would cut power to the batteries. Just my lack of knowledge and experience here. I have minimal user manual info here, so could be more comprehensive info out there.

Happy to hear any recommendations foradditional testing and/or comments on the testing I've accomplished. I don't have any shame OR pride in what I'm doing here and welcome any assistance.

Thanks, Ron
 
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