best conv/charger

[70tincan]

What is the best convert./charger for boon docking and maintaining several agm batteries. Also want to be able to charge off solar some down the road. Will most likely have 2 AC units and led 12v lighting. I have a 7000 EU Honda that I will haul in the truck for off-grid power and charging.

[HowieE]

It is hard to beat the Progressive 9000 series with a charge monitor.

[vswingfield]

Originally Posted by HowieE

It is hard to beat the Progressive 9000 series with a charge monitor.

+1

Progressive Dynamics, the 9000 series in particular, are the best I've ever owned.

Of course my sample size is small, only 2. An older one in the Trade Wind and a 9280 in the Excella. Both have been perfect and required no further attention.

[uncle_bob]

Hi

Whatever you get, make sure it comes with a temperature probe to measure battery temperature. More than any other feature, that will improve your overall experience.

Bob

[70tincan]

Thanks for the info. Do agm have temp issues?

[sgschwend]

The temperature helps the charger reach the correct charge based on the battery temperature. The ones I have observed connect the probe to the battery post.

[70tincan]

would this be a better choice than just the conv.
The Ultimate All-In-One 240V, 50 Amp AC/DC Distribution Panel with built-in Charge Wizard® -
http://www.progressivedyn.com/all_in_one_pd4500_1.html

[uncle_bob]

Originally Posted by 70tincan

Thanks for the info. Do agm have temp issues?

Hi

All batteries are chemical devices. Their voltages vary depending on the reactions involved. That gives them all a temperature dependence. The variation on anything you would put in an RV is enough to make temperature compensation worth doing. Decades ago it was an expensive thing to do and nobody could afford it. Today the probes are cheap and the better controllers all support probes. The only real issue is the hassle of getting the probe out by the batteries.

Bob

[rodsterinfl]

It seems that it would depend on the battery type you plan to have. Lead Acid/Gel or Lithium.

As others have stated, Progressive Dynamics is one to check out. Those that have a 30 amp lead acid/gel (lead acid/AGM) system, the PD4655 lower replacement will do the trick nicely. You get the features of the 9200 and it works with the Circuit Board of the Parallax. It has the electronic protection circuits, the temp monitoring and the manual intervention Wizard part. I haven't hooked up the temp probe due to wiring but it can handle it.

[uncle_bob]

Hi

Decide on a battery bank size first, then pick the type, then pick the charger. Why do it this way? Size in usable AH is what you need / want as an end result. Working that out initially is the rational way to start. Battery type gets into battery cost. Without a target capacity, you will have a very hard time on the A vs B decisions that always get into battery choices. The charger comes last because it's actually not the best thing to buy a charger that's to small or to large. Lead Acid's actually do better if charged fairly hard. A 250AH bank will live a bit longer with a 50A charger (charge at capacity / 5) compared to a 25A charger (charge at capacity / 10). The other factor is that part of your converter output will not go to the batteries. It will be powering other "stuff". A 50A converter may only be putting 30 or 40A into the batteries ( ... how many lights and fans do you have turned on? ) .

Yes, lots of variables ...

Bob

[70tincan]

I was looking into 2 6v agm at 250ah each. Then the 75 or 90 amp all in one deal from PD that I posted the link to. Thoughts?

[uncle_bob]

Hi

First question with any battery is going to be "does it fit?". I'm not a fan of putting lead acid batteries indoors. Your cheap / simple / junk batteries are likely to be around 80AH each so you have 160AH for some number of dollars, some weight, and some volume. They may or may not last as long as more expensive batteries. Is it worth the cost (money,space, weight) to go up to 200AH, 220AH or 250AH? At 240AH you would have 50% more power than the dirt cheap batteries. Do AGM's last enough longer to justify the cost? There's a lot of debate on that. At the end of the day, it's you who will make the decision if the cost is justified or not. There's nothing *wrong* with more power or a better setup other than the cost. Series is a better way to set things up.

Bob

[70tincan]

I will be doing a lot of off grid camping and don't want to have to run the gen. as often. Agm are less maint. and can be discharged more without damage. I have some in my remote cabin and they are a lot less headache. Wouldn't a 6v at 250ah have 500ah when paired in a 12v system?

[uncle_bob]

Originally Posted by 70tincan

I will be doing a lot of off grid camping and don't want to have to run the gen. as often. Agm are less maint. and can be discharged more without damage. I have some in my remote cabin and they are a lot less headache. Wouldn't a 6v at 250ah have 500ah when paired in a 12v system?

Hi

There are a pretty wide range of flooded cell manufacturers and several people make AGM's. Some do it better than others. You can get good AGM's. If you compare them to a lousy brand of flood cells, they will look tremendous. Sorting out who's who in flooded cells on a forum like this gets into nonsense pretty quickly. I'm not going there ...

If you have two 250A 6V batteries in series to get 12V, you will have 250AH at 12V as a result. If you have four 6V batteries in series / parallel to get 12V, then you will get 500AH. Any time you put batteries in series or in parallel you want to use identical batteries. Same make / model / manufacture date. That's going to give you the longest life. If they aren't all the same, the weakest battery in the bunch will either die first and/or kill the rest of them while it dies.

If you are going for a fancy setup, putting all of the 6V batteries in series to get 24V at 250AH is not a bad idea. Going to eight at 48V works as well. If you have the choice, putting batteries in series is better than putting them in parallel. They will equalize out better this way. That gives you longer life and more capacity.

On a 24V or 48V system, your inverter runs straight off of the battery stack. Your charger(s) run straight in at battery voltage. A lot of boats run higher voltage systems, so stuff like led lights, cook tops, pumps and fridges that run off of 24V do exist. There is a bit less selection at 48V.

Since matching things does matter. Something like a GPL-8DL 12V 255AH single block AGM probably will last longer than various batteries set up as pairs or quads. It's a big clunker and not cheap or easy to lift. There's not a practical way to say it's 22.38% longer lived. Batteries aren't that consistent.

Lots of choices.

Bob

[70tincan]

Thanks for the info. I'm going with some pretty good agm. The old saying buying quality only hurts once. I have been pretty pleased with the ones I have at my cabin. I may look at doing 4 smaller 6v in series/parallel to get more AH.