Getting to that magic 14.8 v with an RV Charge Controller

[Wet_Coast]

Hi all, there have been some really constructive discussions in a number of threads in the past couple of weeks regarding battery voltages.

The threads have a re-ocurring theme. Get your batteries to the magic 14.8 volts. While this can be done with a manual charger and a good eye, it's hard to do with the "automatic" charger controllers.. I wish I had found certain material before I coughed up for the PD9160!

I installed my Charge Wizard this morning and found in the super duper charging mode I am getting 14.36, not even 14.4v. Too bad the pessimistic engineers didn't go even a couple of decimal points higher to match their specs!

Is there any way to tweak, say a Progressive Dynamics or other manufactures charger that is "off warranty"?

The PD9160 seems to have some of the case pop riveted. Haven't looked too close as I thought I would ask the question before venturing forth myself. While folks say there may be a way to adjust things, there is no material on how to with the various controllers, RV or solar.

Regardless, my Tracer solar controller according to the spec sheet is supposed to 14.8v. What I am thinking until I can have my technology evolve, is rely on the PD9160 to get it at least to 14.37 and not 14.4 they claim and have the solar get it to 14.8v top it off after.

As well, I went through Handy Bob's material.
Handy Bob's Solar Blog. Unfortunately, he does not mention any under the hood stuff either. Boy, I would love to have a chat with him at the fire one evening!

So learned propeller heads, is there a easy way to adjust the PD chargers to get them to 14.8?

thanks

[KJINTF]

A simple resister change can up the Boost voltage from the typical 14.4 to 14.8
Should not take more than 30 minutes for a competent technician

[MEXICOWANDERER]

I start off running with gusto. Twenty feet later I fall flat on my face.

People ask me if I can run...

I reply "Oh hell yes!"

[64thunderbolt]

My Boondocker starts off @ 14.8. It will bring them up fairly quickly.

[Salvo]

Have you tried using 2 Megawatts with diodes to output twice the current? I'm not sure it will work.

NinerBikes wrote:

If you want to run a pair of MegaWatts through a Schotky diode and lose .4V off the top of the 15.4 to 15.5V a MegaWatt is capable of, then so be it, but then you can pair a set of them for 60 amps, or 72 Amp capacity.

[MEXICOWANDERER]

Like I said going into this on this forum the hydrometer is The Boss. All else is Fuzzy Logic and if you are not familiar with that legitimate term I suggest you WikiPedia it. Chemistry and fuzzy logic don't get along.

[NinerBikes]

To my knowledge, when off the grid, and on a generator, charging with a switching power supply set at 14.8V, there is only one thing limiting the amount of current it will send into the battery.

That would be the battery or batteries resistance to taking a charge based solely on the battery chemistry and how much sulfur is still on the plates, and not in ionic form as sulfuric acid in the electrolyte.

So the PSU sends only what the battery chemistry can take. That is it, that is the limiting factor. I am, of course, comparing a 36 amp or 30 amp PSU to a 36 or 30 amp PD, or Iota. If you want to run a pair of MegaWatts through a Schotky diode and lose .4V off the top of the 15.4 to 15.5V a MegaWatt is capable of, then so be it, but then you can pair a set of them for 60 amps, or 72 Amp capacity.

Compare the amps you get for the price of $50 or $60 for 30 or 36 amps, to any other PD or iota of like amperage, then get back to me with what you paid for your PD or Iota for the same amps. I think in the smaller sizes, you'll find the price per charging amp to be quite a value.

Caveat: I run off a small 158 Amp hr AGM now, it's resistance is a lot lower than the Trojan T-1275 I had previously. The T-1275 ate 14.8V like nothing. It was beat up and sulfated when I got it. I routinely thought nothing of whacking it with 15.0V and 16.0V when I got it, to clean it up, top charge, it, then equalize charge it. It took 3 attempts and about a week, with days in between, to finally get the last cells SG up to where it was correct, with a manual battery charger.

The AGM is like nothing I've ever seen before, it's capacity for amps during charging when below 85 or 90% is hard for me to comprehend right now, even at only 13.5V, the recommended bulk charge voltage.

14.8V is only the magic number if your battery manufacturer says it is the magic number. Don't forget the Screwy 31 by US battery had a recommended top charging voltage of 15.3V. The battery manufacturer has final say for magic voltage, not the charger manufacturer.

[Salvo]

For how long do you get 58A? The PD measured above also output 58A for about 10 seconds. After 30 min the current was 45A and converter voltage was at 14.2V.

That's fine if you're predominately on shore power. But if you're operating the gen, then it's a whole different ball game.

otrfun wrote:
Looks pretty good to me. I also use a PD9260.

Although I try to appreciate the various discussions about different charge voltages, for my layman needs I'm much more concerned about getting the proper charge current.

With my batteries discharged to 12.2v, my PD9260 produces almost 58 amps of initial charge current (measured using a clamp-on ammeter). It's rated at 60 amps. No complaints here.

[westend]

Wouldn't it be possible to use a boost converter with the PD charger to get that last .4 VDC? Also, I would think someone familiar with power supplies could tweak the voltage within but that might be pushing the components to an early demise.
AFAIK, the independent power supplies (Megawatt/Meanwell) are the easiest solution for achieving the higher voltages needed for 6V GC2 batteries.

I programmed my Morningstar solar controller to do the brain work. It must be doing good work as the SG levels are at baseline while in storage.

[otrfun]

Salvo wrote:
Amusing!

There are quite a few people out there that are smarter than the PD EEs.

What's wrong with this picture?



After 240 min, the PD finally gets up to 14.4V. Current tapers from the get go.

14.8V spec

RJsfishin wrote:
If Voltage needed to be higher than 14,4, PD would have made it that way.
Are you all smarter than the PD engineers,....or just think you are.

Looks pretty good to me. I also use a PD9260.

Although I try to appreciate the various discussions about different charge voltages, for my layman needs I'm much more concerned about getting the proper charge current.

With my batteries discharged to 12.2v, my PD9260 produces almost 58 amps of initial charge current (measured using a clamp-on ammeter). It's rated at 60 amps. No complaints here.

[MEXICOWANDERER]

I've tried. I really have. Then I get to laughing so hard I cannot even see the micro keyboard on this smartphone never mind deal with trying to micro touch them.

Example of speech recognition comprehension and I quote

the electrical engineer is not sufficient design or diagnose a battery charging circuit nor a battery diagnostics circuit. an electrical engineer with a chemical engineering degree is almost mandatory larger corporations battery manufacturers use a combination team of electrical and chemical engineers mostly chemical engineers when they manufacture batteries both teams have meetings to decide whom or which of the theories they arrive at is the one to prevail. a tiny company in like a battery charger or tender is not able to have $100,000 a year Electrical engineer nevermind a chemical engineer with degrees. what makes me doubt that the circuit boards for these small Digital chargers are indeed manufactured in the USA? You're going to pay an MEE a hundred grand a year to sit on his duff? These people CONTRACT the design work. THEY HAVE TO NO CHOICE if they wanf to earn a UL or ETL certification label. I used discarded aerospace engineers to help me. So the idea of SUPER WHAPPO converters being housed in a 5-story edifice has to get somehow a grasp on reality. A Technician is a far cry from a degreed engineer and I can tell you for a fact I did not see a lot of familar faces between my electrical, chemical and business administration classes. Gaggles of engineers are a disaster anyway. The half dozen or so PhD eggheads I tangled with at Burbank was dominated by a senior aeronautical engineer who browbeat the others and Lockheed that his whizzpoof emergency battery bank charger was the cat's ---. I had to create a White Paper (where an engineer puts his career on the line) to allow the Skunk Works to adopt a device that was not a battery destroyer. Lockheed paid slow like all giant companies. But they paid through the snot box.

Until someone VISITS one of these battery charger companies and knows a wheelbarrow full of horse---- from rhetoric there is no way to know if a "Design Improvement" does not mean a Transpacific cconference telephone call.

Nuff Said

[Salvo]

Far from king; at least if it can only output 36A.

The gen will run a long, long time.

NinerBikes wrote:
A MegaWatt, or a Meanwell, or a Borg charger is King, only if the owner is diligent about temperature corrections, charging manually, and wanting to optimize the most time efficient use and fuel use of their generator. Once you know your usage, and SOC, you set a timer for the generator... nothing wasted. Pure efficiency. Very little waste. Add solar panel setup for top charge capabilities.

[NinerBikes]

MEXICOWANDERER wrote:
Or, a person can get smart, check into a hotel and wait for the lights to go out (down here).

This forum has what, three or four factions? Some members of each faction insist the idol they pray to is the right one and all others are blasphemy. Sound familiar?

Give battery maintenence your best shot. There are alternative methods available
But as one of my heros Albert Einstein quoted "Insanity can be defined by doing something over and over exactly the same way and expecting different results".

How would you define the factions?

[MEXICOWANDERER]

Or, a person can get smart, check into a hotel and wait for the lights to go out (down here).

This forum has what, three or four factions? Some members of each faction insist the idol they pray to is the right one and all others are blasphemy. Sound familiar?

Give battery maintenence your best shot. There are alternative methods available
But as one of my heros Albert Einstein quoted "Insanity can be defined by doing something over and over exactly the same way and expecting different results".

[NinerBikes]

RJsfishin wrote:
If Voltage needed to be higher than 14,4, PD would have made it that way.
Are you all smarter than the PD engineers,....or just think you are.
And if you want higher voltage, both my little schumachers go to 15.4 for several hrs before float.
My bigger Schumacher goes to 16+ volts before dropping stage.
My tender only goes to 14.4.
Both my stanleys only go to 13.8, then drop to 12.9.
They all have different ideas, w/ PD being the very best, not IMO, FACT !!

When it comes to correct bulk charge voltages:

There are PD engineers with ideas on what is correct. There are PD accountants with ideas on what are correct, but the ultimate say is what gets passed by PD lawyers to prevent lawsuits, and they overrule Engineers and Accountants.

And the Lawyers are the ones that say go with 14.4V. Nobody else. Around here, the experts that were in the industry as consultants say 14.8V at 25C, or 77F.

Which is why Iota makes 14.7V possible, plus Iota is made in very hot AZ, not polar frozen p*ssy charging voltage Michigan, where the voltage would need to be even HIGHER for bulk charging due to the colder weather.

Maybe you should ask a US Navy sub battery maintainer if still alive, what the proper charge voltage is per cell. Multiply by 6 for a 12V battery.

Compared to a WTFCo, a PD is a huge improvement. An Iota with the 14.7V loop cable in place is better,for bulk charging operations. A MegaWatt, or a Meanwell, or a Borg charger is King, only if the owner is diligent about temperature corrections, charging manually, and wanting to optimize the most time efficient use and fuel use of their generator. Once you know your usage, and SOC, you set a timer for the generator... nothing wasted. Pure efficiency. Very little waste. Add solar panel setup for top charge capabilities.

As has always been the case, if you aren't in the masses, who are azzes, and you want something done RIGHT, you gotta do it yourself.

RJ, since you have so many battery chargers, why not add one more. Pick up a Mega Watt S-400-12 from the shop in Aqua Dulce, CA, and a RC chargemeter off of Ebay. Cobble your unit together, set it at 14.8V. Then next winter, start using it with your EU1000i in the morning, no solar panels involved and log your results. Get back to us then, maybe we can make a believer out of you yet.

BTW, now that I have an AGM Teleco surplus 158AH battery, with the MegaWatt, I don't need a new charge controller, due to it's different, lower resistance and lower charge voltage battery requirements, compared to flooded lead acid batteries. There's more savings right there, with a manual MegaWatt for a battery charger. Manufacturer says charge at 13.5V What are the PD engineers going to do about that?

It's like saying one shoe size fits all. Utter BS, at least, not properly, but maybe in a 3rd world nation, that's good enough.