What I learned about maintaining batteries while boondocking

[TooTall2]

To charge with the onboard or use an external stand alone charger. Here's what I concluded during my week of boondocking.

https://youtu.be/IgQTtnEXlU4

[BFL13]

If you are going to spend that much for an ammeter, you would do better with a Trimetric monitor, which will also do your AH tally, which is very useful while camping.

The clamp-on ammeter does not do AH counting. Also you want to be able to measure say 200 amps or so, which not all ammeters can handle.

[profdant139]

TooTall, thanks for that post. To a non-expert like myself, the most interesting part of your video was your use of the clamp-on ammeter to verify the amperage in real time and then to compare the reading from the stand-alone charger to the reading from the built-in converter.

I think it's time for me to get one of those devices, rather than relying solely on my multimeter. After doing a little on-line window shopping, I am amazed at how much the prices vary -- from the $30 range to over $300! I guess it is like anything else -- you get what you pay for -- but I wonder whether a very casual user (like me) can get away with the cheap version.

[BFL13]

If 14.4 is the upper safe limit then please inform Trojan Battery (and others) that their specified charging voltage of 14.8 is unsafe.

Also note that 14.8 is at 77F. At 35F the equivalent voltage is 15.2, which is of course, over 15.

To achieve these correct voltages, you will need an adjustable voltage charger, or have temperature compensation. The standard RV converter can't do them.

[Chuck_thehammer]

in the 12 volt world... 13.6 is standard charging.. 14.4 is upper SAFE limit... anything over 15 is bad...

that being said.. some but NOT all will live to 15.5... not over.

most batteries "IT" will put added heat in cells and may boil out water.. but electronics can and will DIE.

[BFL13]

IMO since the batts were accepting 17 amps at say 14.4v from the portable, they should have been accepting more than the stated 3 amps at (assumed) 13.6v from the WFCO.

Before just replacing the WFCO in place, the wiring etc should be checked over, or else any new converter will also under-perform badly.

Alternatively, the gen looks like a 2400w, which will run up to a 75 amp charger, so there is no need to use a teeny- weeny "12a" charger with that gen if you want a fast recharge.

I would take both routes.

1. Get a bigger charger ( I would choose the PowerMax 75A ADJ model--but not the regular converter, ONLY the adjustable voltage version), and

2. Find out what's wrong with the WFCO installation, so it does more amps at 13.6, even if it never does 14.4.

Then, I would use the WFCO on shore power and at home on Float, and use the big amp charger when off-grid and running the generator.

EDIT--yes 16v is way too high! Don't do that. Norcold fridge limit is 15.4v, EG.

[DanNJanice]

Just curious, is anyone concerned about the high voltage output from these fast chargers? I know the smart charger that I have at home ramps up to 16V when it is charging. Is there a chance that other electronic devices could be damaged if used while charging?

[Sandia_Man]

Those experienced with WFCO converters have for years expounded on their anemic performance, particularly with their inability to quickly recharge a depleted battery. Any reputable smart converter would trash that portable charger, when camping off the grid nothing is more paramount than restoring consumed amphours quickly and efficiently.

Contact Randy at BestConverter.com for an easy upgrade option to a smart converter, along with your generator, it'll make for worry free RVing off the power grid. Although we have solar which is by far the most efficient, it is secondary to our genny and smart converter in making us fully self-contained, regardless of where we are parked or whatever the weather brings.

[gbopp]

Good to know. Thanks for posting.

[12thgenusa]

There are a several things to consider when making a comparison. What was your battery SOC? How large is your battery bank?

I have a 55 amp WFCO and it will put out 65 amps if the SOC is around 50% and 30+ amps at 85% SOC.

I also have a 35amp stand alone charger. If charging from a generator, which is rare, I will use the charger since my 1kw generator won't support the WFCO full bore with its poor power factor.

[Boon_Docker]

That is an awesome charger!
It is rated at 12 amp fast charge, but it can put a 17 amp charge into the battery.

[Sam_Spade]

Your comparison of an inexpensive single stage charger (OEM) versus a charger with a better design (at least 2 stages) is spot on.

For convenience, a lot of RV owners elect to mount the better charger in the vehicle permanently.....by replacing the OEM converter with a better one.