Solar Battery Controller Settings

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.

BruceK

Moderator Emeritus
Joined
Oct 31, 2011
Messages
13,347
Vessel Name
Sojourn
Vessel Make
Integrity 386
I`m after the correct settings for Bulk Charge and Float voltage for flooded lead acid batts. The charge is via a controller for PVs.
The instruction manual says for flooded lead acid: Bulk 14.8v; Float 13.5v. (For sealed gel type lead/acid it says 14.3 and 13.5 respectively.)
If a wet lead acid is normally fully charged at 12.6+(Ed Sherman), those values seem too high, suggesting the charger would be "boiling" the batteries. So I set Bulk at 13.6v and Float 13.2v, but it`s easy to reset them.
While on the subject, the controller has an equalization phase. I turned it off, my understanding is it kicks sulphation off the plates back into solution and that sulphation is caused by chronic undercharging, which the panels effectively prevent.
Thoughts?
 
The settings will vary depending on weather the boat is being operated.

The higher Voltages suggested are perfect for cruising , where you are exercising the batts daily and they will spend considerable time at less than FULL 100% charge.

Water consumption is expected when operating , and recharging from a modest discharge..

For the times when the vessel is NOT being operated .

Dockside for storage or on the hard all winter the voltages can be lowered .

We bulk charge to 14v , but put the Float down to 13.2 or even just 13v when storing , unattended in Fl at our dock.

Slightly overfilling before departure and a friend at the 3 month period keeps the set from running dry ., and will still power the bilge pump as required.

Batterys in use need more charging that those on standby.
 
The voltages in your manual are good for a multi-stage charger. The difference between the 14.8 bulk charge voltage and the 12.6 full charge voltage is the difference between a battery under charge and one that's sitting at rest (no load and no charge).
 
Thanks, I will fine tune when next on the boat. Pretty sure I helped ruin one of the 2 8Ds by somehow setting float too high, but it is 5yrs old, the other is 4yrs. Just bought a new flooded one to fit (ugh), specs of the one delivered exceed those advertised, CCA 1100>1280;Amp 200>225, looks like I scored an upgrade. IG design is one batt serves each engine for start and house, they get auto combined for starting, I can select either or both on the main switch for house. No dedicated house and start has never been an issue except just after purchase when I discovered how bad the batts were, the genset and charger were my friend.
 
Back
Top Bottom