B2b chargers?

[tx2sturgis]

I had watched a few videos from the van build where they are using solar as a starting battery maintainer...

Yep, it works for me and a lot cheaper than the b2b bidness.

 

[bullfrog]

The more solar the better!

 

[highdesertranger]

yes I have done the small solar for the starter battery too. highdesertranger

 

[B and C]

Yep, I went with a small solar panel and charge controller:  https://www.amazon.com/gp/product/B00PFG56ZS/ref=ppx_yo_dt_b_detailpage_o05_s01?ie=UTF8&psc=1

10 watt panel and 3 amp charge controller with these https://www.amazon.com/gp/product/B00NEWBGR2/ref=ppx_yo_dt_b_detailpage_o05_s01?ie=UTF8&psc=1 spliced in for disconnects.

 

[ZoNiE]

Following this. I want to be able to keep my starting batteries topped up from the house bank which is on solar. Then I can leave the computer that I use for the engine management turned on all the time.

 

[bullfrog]

Just courious, why would you want to keep it on all the time and how many amps are leaving you start battery with the key off? Could you not power it directly from the house battery side of the isolation relay and do the same thing?

 

[gapper2]

Yep, it works for me and a lot cheaper than the b2b bidness.



tx2sturgis,  I don't think b2b's keep starter battery charged.  I know mine doesn't.  BB1260

 

[frater secessus]

I think I read in the CTEK manual that their alt+solar B2b does that. The power for it comes from the solar side.

 

[tx2sturgis]

tx2sturgis,  I don't think b2b's keep starter battery charged.  I know mine doesn't.  BB1260

I was responding to a post by bullfrog about a solar-powered maintainer for a starter battery, and some of the other posts here, that have alluded to charging both a starter battery and the house batteries using a b2b unit.

 

[ZoNiE]

I could connect the computer to the house side, just wanted to keep it all on the same "side" of things. There are other things in the coach that drain the battery, such as the in dash stereo, and the engine and transmission management computers. The 100A panel on the roof that is OEM is now 23 years old.

The computer is just a Mac-Mini with a 12V power supply.

 

[WalkaboutTed]

I Have the CTEK D250S and SmartPass on two vehicles. They work well and though we have separate charge controllers for the permanent solar, I have plugs set up for portable solar. Which I haven't used since I went on the road in 10/2017. Even cloudy and rainy days I get back to full by mid afternoon. Negatives to the CTEK units? Expensive and non-adjustable.

Would I go with the CTEK system again? Yes. I just wish it were adjustable. But they work well.
Ted

 

[gapper2]

"I Have the CTEK D250S and SmartPass on two vehicles. They work well and though we have separate charge controllers for the permanent solar, I have plugs set up for portable solar. Which I haven't used since I went on the road in 10/2017.  Even cloudy and rainy days I get back to full by mid afternoon. Negatives to the CTEK units? Expensive and non-adjustable."

My BB1260 was expensive and adjustable and has no solar input but I have a solar controller to handle that.  I use a switch setting to keep my starter battery charged.  I paid $30 more than what the blue sea 7622 cost on amazon this morning which is what the OP was originally considering. Got to do your shopping.

My purchase decision was based on a future lithium house battery purchase and the AMP starved Odyssey batteries I now have.


One thing to consider is whether your alternator can handle the strain.  As Half Shadow mentioned in a earlier post without some way of limiting your current flow other than a very fickle alternator internal voltage regulator, you run a good chance of destroying your alternator with a battery bank such as lithium or even the AGM's I have.

I ran a test yesterday.  My battery bank 200 AH AGM's were down to 78% from full.  I used a 100 amp capable manual charger from shore power. The batteries took in 76 amps on the bulk portion of the charge and took over an hour to get to an absorption voltage.  3 more hours to get to 100% as measured by an ending current of .4 amps.  That kind of unrestricted initial current flow would probably destroy most stock alternators without VERY careful monitoring.  And will probably have me looking into a future alternator upgrade.

The b2b I have is certainly not for everyone.  It has to be mounted indoors.  It's fairly large.  And the controls are somewhat cryptic.  but if you have no problem with pushing buttons (or mashing buttons as we say in the south ) you won't have too much trouble

Another thing to consider is the wire run from starter to house battery to answer the OP's question from another post.    For my unit the manuacturer recommended 4 AWG.  For an isolator or relay setup that would probably be much larger.

With the ability to use the alternator as a programmable multistage charger and to limit the current to a safe level for my alternator, I am happy with my purchase even though I will probably need a larger alternator soon.  Can you say "More money"? :-/

 

[tx2sturgis]

Gapper2, can you place your replies (after quotes) just under the quoted text box please, it makes it much easier for us to understand what is quoted and where your reply starts, and makes it easier for us to quote you in any reply we post.

Thanks.

 

[gapper2]

Sorry Tex,  I was wondering what that box was.   I really am a freak that doesn't post much.   Kinda new to forums.  Thanks for pointing that out otherwise I could have gone no telling how long doing the same darn thing.

Maybe one of the mods will straighten that mess out