Synchronizing Solar Outback and Multiplus

[Pelagic]

I am trying to figure out WHY both the Outback Solar Charger and my Victron Multi charger are going into absorbtion phase earlier and earlier since we have been off of shore power for the last 3 months.

Now the chargers are going into absorbtion at 85% SOC and Float at 88%
Tending lower and lower over the last 2 months

Before Solar was taking me to around 100% before going into float stage as was the Victron Charger.

Is it a battery issue or a synchronization problem?

BMV600 and OUTBACK Settings:

Cb 0926
Vc 026.4
It 0.2.0%
Tcd 0.3
CEF 90%
PC 1.25
Ith 0.01a
Tdt 0.31
DF 50.0%
CIS 90.0%
RME 0
RDD 0
Trojan Battery's response:
.Peukert value is 1.23.

[sailorboy1]

I don't understand really. My Outback controller doesn't "go" into absorption, it slowly increases voltage in Bulk till it reaches absorption and then stays there for the hours programed or till it hits the low amps programed and then goes into bulk.

It just raises the charge till it gets to the absorption voltage and then holds that. What is the amps the battery is accepting at the end of the absorption phase?

I bet it is just the BMV600 is not in syn and needs to be reset to 100% (assuming they are at 1100% based on acceptance). Or since you say it is going into float at 88% SOC that the absorption time needs to be increased.

[tanglewood]

I'd guess that either the SOC meter has drifted off, or that you have accumulating sulfation. As sulfate builds up, the batteries will appear to reach absorb and full charge earlier and earlier, even thought they haven't actually accepted full charge. Sounds like it's time for an equalize charge, if you have the means to do it while off shore power.

[coopec43]

Any clues here?


Solar Outback 80 programming Tips
http://www.cruisersforum.com/forums/...ps-202035.html

[Pelagic]

Originally Posted by coopec43

Any clues here?


Solar Outback 80 programming Tips
http://www.cruisersforum.com/forums/...ps-202035.html

Thanks coopec for reminding me of that discussion when I first connected Solar. I had to reposition BVM 600 Shunt direct to batteries from where it was on Buss Bar prior to Solar.
At that time. I did not play with the Outback programing as the experience from Bill, who overcharged and killed his AGM's, intimidated me.

I will get on shore power and try to get up to 100% by battery charger alone, then start again with programing charger and solar to complement each other

[sailorboy1]

Originally Posted by Pelagic

I will get on shore power and try to get up to 100% by battery charger alone, then start again with programing charger and solar to complement each other

Start first by just going into the Outback advanced menu and changing the absorption time to something like 6 hours and the end amps to something like 2 amps and let it charge the batteries fully. When the amps get down to less than 0.5% of your amp-hour capacity check your battery monitor and reset it.

If you don't think your solar can get to 100% by itself just run the engine/generator in morning till battery acceptance gets down to whatever your experience says that the solar can put out and then let the solar do it.

[noelex 77]

Sorry Pelagic, I do not understand the settings you have listed. Perhaps you could present the important parameters in a different way?

The transition between absorption and float is complicated and depends on a number of settings. However, it interesting that you feel the transition between bulk and absorption is also inappropriate. This is a very simple transition that is only controlled by the absortion voltage. As it such a simple transition, it is easy to troubleshoot.

Of course the higher the charge current, the quicker the batteries will reach absorption voltage. So with a higher charge current from multiple charge sources, the absorption phase will be reached at a lower SOC. This is normal and does not indicate any problem with the charge settings or the batteries, but your post suggests the problem may be more than this.

So if the absorption transition is occuring prematurely, the only possibilities are:

1. The absortion voltage is incorrect
2. There is excessive voltage drop (wiring that is too thin or a connection, switch etc has developed a high resistance). In this case the absorption voltage at the batteries will be lower than at the controller, so the controller will enter the absorption phase early.
3. The batteries (or a single battery in the bank) are defective.

The final possibility is that the transition point is correct, but the battery monitor is incorrect, or out of sync, giving the impression that there is a problem.