FLA charging voltages

[sailorboy1]

I need to fine tune my solar controller settings. Over the years I've read lots of voltages for various charging stages, so:

Absorption - Penn says my Dekka batteries absorption charge should be 14.1. But I know from past alternator charging that 14.1 doesn't seem to cut it and I've read people say it should be 14.6-14.8. My default on the controller is 14.4. What says those in the know?

Float -the default is 13.6, which again is more than Penn says (13.5)

Equalize - the controller default is 14.4 again, which doesn't seem to be anything other than a longer absorption. Suggestions for max voltage.

And on the absorption I can program a minimum charge time and the default is 1 hour. Penn says that 1 hour at absorption if discharge is <25% of AH capacity, so I can change this as needed once I get more usage info. But is there a problem with doing 2 hours regardless (except maybe gassing)?

I hope to not regret asking instead of doing what I believe the answers are.

[dandrews]

Originally Posted by Don L

I need to fine tune my solar controller settings. Over the years I've read lots of voltages for various charging stages, so:

I hope to not regret asking instead of doing what I believe the answers are.

Not as long as you don't mind 20+ different opinions. :-)

Don

[sailinglegend]

Originally Posted by dandrews

Not as long as you don't mind 20+ different opinions...

You won't get any sensible answers unless you tell everybody what batteries you have!!!! FLA, Sealed, Calcium, AGM, Gel?

The answer is always to go with what the manufacturer says. Their voltages would indicate you have Gel batteries.

The absorption time setting will depend on what size battery bank, chargers, alternators, Solar? The bottom line here is set the absorption time for as long as it takes to get the charge current into the batteries at 1% or less of the bank capacity at the absorption voltage. With good regulators there may be another 10 settings that can also be changed - with care!

[sailorboy1]

Originally Posted by sailinglegend

You won't get any sensible answers unless you tell everybody what batteries you have!!!! FLA, Sealed, Calcium, AGM, Gel?

gee I wonder what the thread title is

[Albro359]

Why don't you tell us what you have rather tan being obscure?
IF FLA means Flooded Lead Acid batteries, then your voltages should be approx.
Absorption 14.4
Float 13.3
Equalise 15.5
Absorption time is trial and error, to get to max charge status as said before, dependent on bank size, alternator size etc...

There's plenty of stuff on here about that... try searching other threads

[Maine Sail]

Originally Posted by Don L

I need to fine tune my solar controller settings. Over the years I've read lots of voltages for various charging stages, so:

Absorption - Penn says my Dekka batteries absorption charge should be 14.1. But I know from past alternator charging that 14.1 doesn't seem to cut it and I've read people say it should be 14.6-14.8. My default on the controller is 14.4. What says those in the know?

Float -the default is 13.6, which again is more than Penn says (13.5)

Equalize - the controller default is 14.4 again, which doesn't seem to be anything other than a longer absorption. Suggestions for max voltage.

And on the absorption I can program a minimum charge time and the default is 1 hour. Penn says that 1 hour at absorption if discharge is <25% of AH capacity, so I can change this as needed once I get more usage info. But is there a problem with doing 2 hours regardless (except maybe gassing)?

I hope to not regret asking instead of doing what I believe the answers are.

Don,

For the FLA deep cycle Deka/East Penn batteries they recommend:

ABSORPTION - 14.4V (2.40 VPC) - 14.7V (2.45 VPC) - Max absorption time = 12 Hours)

FLOAT - 13.8V (2.30 VPC) - 14.1V (2.35 VPC) - Max float time = No Limit

EQUALIZATION - 15.0V (2.50 VPC) - 15.3V (2.55 VPC)

[sailorboy1]

Originally Posted by Maine Sail

Don,

For the FLA deep cycle Deka/East Penn batteries they recommend:

ABSORPTION - 14.4V (2.40 VPC) - 14.7V (2.45 VPC) - Max absorption time = 12 Hours)

FLOAT - 13.8V (2.30 VPC) - 14.1V (2.35 VPC) - Max float time = No Limit

EQUALIZATION - 15.0V (2.50 VPC) - 15.3V (2.55 VPC)

Where did you get these numbers as they differ from what they sent me (attached)?

Sometimes I wish I had never read some things so I didn't know of the differences.

[hellosailor]

Don, I would go with the numbers that the battery maker supplies, since the chemistry each maker uses is a little different and their numbers will reflect that.

Then there's the question of numbers: You are dealing with 0.3v differences as being significant. Are you using calibrated meter(s) or are you certain that what you are reading is the actual voltage? I would suggest that an uncalibrated meter can easily be off by 0.2v out of the box, or drift that far off after it has aged a couple of years.

Accepting the numbers without confirming calibration, can be a snark hunt.

[sailorboy1]

Originally Posted by hellosailor

Accepting the numbers without confirming calibration, can be a snark hunt.

I'm pretty sure I'm getting a good voltage reading. I have 4 ways to read it and they all agree.

I think I'm just going to go:
14.6V absorption
13.6V float
15.2V equalize

I'm going to stay with the 1 hour minimum for absorption but will also program in 4 amp floor for absorption that if the current gets down to it will put the system into float (the refrig would have to cycle off).

[Maine Sail]

Originally Posted by Don L

Where did you get these numbers as they differ from what they sent me (attached)?

Sometimes I wish I had never read some things so I didn't know of the differences.

Don,

That is an old sheet that, according to at least one inside support person at Deka, was changed & updated due to some errors.

The new sheet went up in 2012. This covers the marine market as well..

Deka Charging Paramaters

[sailorboy1]

Originally Posted by Maine Sail

Don,

That is an old sheet that, according to at least one inside support person at Deka, was changed & updated due to some errors.

The new sheet went up in 2012. This covers the marine market as well..

Deka Charging Paramaters

Thanks Maine Sail!

So much easier when you have the right sheet. Of course they sent me the wrong one just a couple months ago.

For some reason I couldn't find on a web search. But once I knew the name I found it almost right off.

And based on their charging parameters, I was right in that I had been using too low a voltage on the batteries since 2 years ago when I got them. I would bet this has been the case on my boat for 12 years since it was new because the regulator was set at the default program.