Dual alternators and dual batteries.... - Page 3

**daveb** · 10-19-2015, 12:15 PM

Actually I don't quite have what I want but maybe I'm over reacting too. When I ordered the high amp alternator I didn't expect the voltage to be so high. I was worried about the Lifeline batteries and according to their tech, those batteries like a slightly lower voltage all around. After re-bussing the battery leads I was still getting 14.6 and sometimes more at the batteries. Lifeline claimed I'd cook those batteries and at 500 bucks a pop I started to worry a bit. But the 6.0 likes a higher FICM/injector voltages from what I've gathered so it put me in a catch 22 situation. I did purchase a high end FICM and a lower voltage XP-270 hoping that with the combination of lower voltage alternator, better FICM and solar charge that things would be good. Maybe I am. The Balmar product is nice but it's expensive and being it regulates the voltage I just wouldn't want it forcing the alternator to put out a low float voltage that's best for the batteries but bad for the engine. Would 13.3 volts be hard on the 6.0 PSD engine? I do understand that you can set the charge parameters to almost anything and what I had planned to look into was having the old alternator set up with a Balmar and have it regulate the voltage to a spread best for both the engine and batteries. Just never got round to it and was a little curious about how the engine bay heat would affect it. Now that I have hood louvers cut in it might not be an issue. Hell maybe the Balmar can handle the heat anyway...I'll have to look into that. The other option is to reinstall the high voltage alternator and use a different product like the Power Stream to let the house batteries get a constant multi stage charging session at the best voltage that gives the batteries their longest life.
Dual alternators are not an option for me cause I have a Starcool system on board. I can see where twin alternators with one being regulated by a Balmar unit would be a great way to go. When I start part two on my engine bullet proofing, I'll have to look at what's best all around.

Viva · 10-19-2015, 01:10 PM

I may be out of my league here, so take this with a grain of salt. At any rate, I hear your concerns, Dave. I, too, have Lifeline AGMs for a house bank, and I treat them regally when they are solar charging (meaning I have custom set points that are just what Lifeline asks for, plus temperature compensation).

On the alternator side, I just have the basic Ford (120 or 130 amp or around that) alternator. V10 gas engine. Looking at the Scan Gauge I see it move between 13.6-14.1 volts or so most of the time. The Lifelines have a lower float spec than most AGM's (it seems) at 13.3 volts. So yeah, I wouldn't feel great about charging them at ~14 volts for hours on end.

The way I've handled it is to use a manual switch for "combining." While I was at it I put in 1/0 cable between start and house battery. I can now comfortably fuse it and still use it for jump starting. What I do is mostly NOT combine. I mean, as long as my solar system is keeping things up to 100% most days, I just leave the alternator out of the "house" picture (leave the switch on "off").

If (like right now) there is a string of cloudy days and my batteries get below 85%, and I'm going to be driving, then I do combine, but only for the bulk/absorb stage. Once the batteries get to about 85% I de-combine again. From what I have read the alternator doesn't do too well at getting that last 15% anyway (which makes sense since I think (?) since float is 13.3 volts for these batteries and the alternator is always putting out more than that). This way I use the alternator mostly for bulk charging and that's all, and don't subject my Lifeline house batteries to higher voltage when they should be in float. When it's sunny out I have no need for it at all and just keep it "off" (de-combined) by default. My start battery doesn't need extra charging so no need for it to go the other way.

Probably something like the Sterling would be the technically better way to go, but I was trying to keep things simpler. So far I'm happy with the system. Situation might be different for someone who doesn't have the solar capacity to keep things up much of the time. If I were driving a lot and had no/little solar, then I think I would look into something like the Sterling B2B and set it up like my solar controller, for the correct set points (I wonder if they have temperature compensation? Haven't checked.)

Just another approach,
Viva

**daveb** · 10-19-2015, 02:59 PM

Which was what I was doing after I installed the higher voltage alternator and saw those voltages Viva. Myself I want things automatic, so I forked out the bucks & stuck in a lower voltage XP-270. The new alternator has a lower voltage of 13.5-13.9 as an average so I just let the solar do the final charging. Seems to work for me and why I haven't been motivated to do any changes. I just don't know about the engine portion of this. If 13.5 to 13.9 volts isn't bad for the FICM/injectors (which I don't know to be true) I'll just leave things as they are. Being I have a practically brand new XP-270 sitting in a box, it would be an option to add better charge regulation and provide a more middle of the road voltage that suits both the engine and battery systems. As mentioned, there are other regulators out there. I had also looked at these:
http://store.alternatorparts.com/v1300- ... -vset.aspx

Balmar products are just higher end marine based stuff and programmable. The power Stream unit would be best for the house batteries but installed so the separator would be normally open and would have to be manually closed to jump start the vehicle. These are all charging solutions and I'm guessing there are more to choose from. But in the back of my head the K.I.S.S. phrase keeps popping up.

Viva · 10-19-2015, 06:11 PM

Quote:

Originally Posted by daveb

But in the back of my head the K.I.S.S. phrase keeps popping up.

That's where I sit. Since I rarely combine, the manual switch is not an issue for me (but I can see where if you want it automatic, you want it automatic, and no harm in that).

Balmar is a familiar name to me since I come from boating, but just for me in the van with solar I (for now at least) don't need alternator charging too much of the time. But horses for courses and there are a lot of different courses in the way we set up our rigs and use them, not to mention personal taste in details.

E350 · 10-21-2015, 07:39 AM

I like to think there are one or two bright pebbles in there but, in reality, I am dumb as a box of rocks when it comes to electrical. (But that has never stopped me from asking stupid questions before...) So, in the spirit of teeing up a question for you guys to deepen the knowledge pool, here goes:

The smartest battery chargers/desulfating maintainers that I am aware of are all run off of AC current. (And based on what I have read from Scalff77's recent posts, the Lithium batteries are only chargeable from AC current chargers.)* **

An alternator produces alternating current. It's in the name. An alternator requires rectifiers in the form of diodes to convert the alternator's ac current to direct current.

So, in the interest of keeping it simpler, does it make sense to run an alternator without diodes into some sort of ac voltage regulator to a smart charger to charge our house batteries?

Leaving aside that that is likely what my Auragen 5kw second alternator does, is there anyone out there making an alternator which produces ac to run a regular smart battery charger?

* After bulk charging it with a Napa Battery Charger, 80/20 - 10/2 Amp; 12 Volt; NBC 85620 (thanks to daveb and Scalff77 from a couple of months ago) and then running the big 12248 Battery Minder (and putting it on every night when we get home from work to continue to desulfate it) I recently put a 15 year old Optima D31M battery into my Bronco where it is starting and running the vehicle just fine.

** And using the same Napa bulk charger and then following it up with the same Battery Minder we have been running our jet skis 3-4 times a week on 5 year old (purchased in 2010 and sat in the skis NEVER used) 12v flooded cell lead acid batteries.

Scalf77 · 10-21-2015, 08:02 AM

Quote:

Originally Posted by E350

The smartest chargers/desulfating maintainers that I am aware of are all run off of AC current. (And based on what I have read from Scalff77's recent posts, the Lithium batteries are only chargeable from AC current chargers.)*

I don't think I said that the only chargers for Lithium were AC. What I said that at the moment, most chargers have no settings for lithium batteries, and even the ones that do, might be wrong as real life data comes in those set points appear to be changing. As with any battery the voltage set points go a long way at getting the most lifespan out of your battery. Since the high cost of lithium becomes more palatable if you can truly get the expected life span out of it. So I said that you would need chargers that let you program the set points.

This thread has pointed out multiple sources that turn a alternator into a good multi phase charger already. There were also other solutions that will work if you have just one alternator that were pointed out. You already have a auragen so you could integrate that into a overall solution with a good AC charger.

I am not sure what your trying say with the Optima battery data .

-greg

E350 · 10-21-2015, 08:21 AM

It was the Lithium battery manufacturer's data sheet which I followed from your link to the RV'ers Lithium experiment, which led me to the conclusion that only an AC battery charger can stay within the Lithium manufacturer's warranty parameters to charge lithium batteries.

The Optima and jet ski batteries were dead. And hallelujah were brought back to life by the Napa bulk charger / Battery Minder sequence. So, I was trying to say that smart chargers/desulfating maintainers really work. Which I thought others might find interesting/useful. And I wanted to say thank you for your and daveb's help with my selection of a bulk battery charger. The Napa automatic charger also has a float to desulfation pulse mode as well as bulk charging. It seems to me that the advancements in lower cost smart chargers are on the AC side not the vehicle alternator side (except possibly from the Sterling). I mentioned my Auragen 5kw because it is an option, but at $5,000 it is an expensive option. That is why I asked if anyone out there knew of a vehicle alternator putting out ac to a regulator to a smart charger.

Edit, to really piss off everyone:

"The basic premise of the Founding Fathers was man's right to his own life, to his own liberty, to the pursuit of his own happiness - which means: man's right to exist for his own sake, neither sacrificing himself to others nor sacrificing others to himself...." - Ayn Rand