6volt batteries questions...

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galladanb

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I bought them in Jan or march, charged them up and then installed them. I guess I did not check the water levels....

Fast forward to now, six months later...

Checked them visually. Saw they needed some water.
All told, I guess I added about a half gallon of distilled water to the cells. That was kinda surprising...

Took a hydrometer reading and they indicated needing recharging, as all cells showed in the red.

So here are some questions...
1.) is it possible the solar controller and the inverter charger are reading each other and then deciding to not charge?
2.) should I isolate each charging system to see if one or the other is failing?
3.) should I isolate all systems and use the garage charger to bring the batteries back up first?
4.) how long should I wait to reuse the hydrometer, to allow the water to mix in properly?

I have so far shut off the charger inverter for now. 
And the fridge is on 110ac meaning I have unplugged the 12v side.

SO I guess right now there is no 12v draw...

It's kinda confusing right now...
 

Trebor English

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You added a half gallon of water to the top of the battery.  The acid is at the bottom.  The water has a specific gravity of 1.0.  

Can you rock the batteries back and forth or drive around some to mix up the acid and water?  I usually just wait a couple of days.  Normal motion getting in and out and moving around inside for a couple of days mixes it up.  

Other than low specific gravity do you have any indication of a problem?
 

Trebor English

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Pick a day.  Today is the second.  Check the water every month on the second.  Maybe you have another more memorable day.  If you skip checking the specific gravity one month that doesn't matter so much but be sure to check the water.  I write down how much each cell takes.  If they aren't using water they aren't getting charged consistently over the month.  I use a 20 ml syringe to measure the amount I put in.  

On the other hand, it seems to work for you to add a half gallon every 6 months.
 

galladanb

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Trebor English said:
You added a half gallon of water to the top of the battery.  The acid is at the bottom.  The water has a specific gravity of 1.0.  

Can you rock the batteries back and forth or drive around some to mix up the acid and water?  I usually just wait a couple of days.  Normal motion getting in and out and moving around inside for a couple of days mixes it up.  

Other than low specific gravity do you have any indication of a problem?

Cool, I will make a couple of Walmart and Best Buy runs. Then recheck.

No other indication, other than thinking as a "mental HUH? " kinda side note when looking at the seemingly low issh voltage indicated by the meter. I think it was around 13.8 at the moment I noticed it....
 

John61CT

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No, checking more frequently is not optional if they're cycling, you really don't want to risk going too low.

Get a nice high-amp shore charger, isolate from all loads, get them to very full at mfg spec'd absorb, trailing amps at .005C (.5A per 100AH)

Then follow mfg's protocol for Equalizing or Conditioning. That will stir everything very nicely, help prevent future sulphation.

Really should do all that monthly for maximum longevity, assuming you do everything else properly could add years.

Not least checking water levels! :cool:
 

John61CT

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Don't worry about multiple concurrent charge sources, long as all within mfg spec charging profile.

Ideally all adjusted the same setpoints, but NBD even if not.
 

galladanb

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Trebor English said:
Pick a day.  Today is the second.  Check the water every month on the second.  Maybe you have another more memorable day.  If you skip checking the specific gravity one month that doesn't matter so much but be sure to check the water.  I write down how much each cell takes.  If they aren't using water they aren't getting charged consistently over the month.  I use a 20 ml syringe to measure the amount I put in.  

On the other hand, it seems to work for you to add a half gallon every 6 months.

Right! Sounds good. I guess I just forgot or was just lazy. It like I knew I should have been checking, but didn't.... I'll try to do better.

And I mentioned a half gallon because I started with a fresh full gallon, and I have about half left...

I guess I'm more worried about the systems not charging the batteries or not?
 

galladanb

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John61CT said:
Don't worry about multiple concurrent charge sources, long as all within mfg spec charging profile.

Ideally all adjusted the same setpoints, but NBD even if not.

The controller and inverter charger are using the factory default settings.
I told the controller the battery set was flooded, but no changes other than that...

Sorry, what does NBD mean?
 

John61CT

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No big deal.

A quality manufacturer will spell out the recommended normal charging setpoints vs equalizing, trailing amps etc.

Otherwise just go with say Trojan's recs.

Or fuggedaboudit, nbd :cool:
 

Weight

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How many batteries were there to use 1/2 gallon? Were the tops of the plates exposed? If so, start saving for new batteries. Shaking or driving will not mix the electrolyte as much as if you just (1) put a charger on the batteries. (2) Then check the SG if you want. (3) Then top the liquid.
 

John61CT

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> The controller and inverter charger are using the factory default settings.

That usually results in premature transition to Float, gross undercharging, murdering the bank early.
 

galladanb

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Weight said:
How many batteries were there to use 1/2 gallon? Were the tops of the plates exposed? If so, start saving for new batteries.  Shaking or driving will not mix the electrolyte as much as if you just (1) put a charger on the batteries. (2) Then check the SG if you want. (3) Then top the liquid.

Two, each 6v
Tops were not exposed
They weren't all that bad, so right, savings are good
Thx for the suggestions!
 

galladanb

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John61CT said:
> The controller and inverter charger are using the factory default settings.

That usually results in premature transition to Float, gross undercharging, murdering the bank early.

For my controller the defaults for flooded batteries are as follows...
EQ voltage 14.8
Boost voltage 14.6
Float 13.8
EQ duration 2 hours
Boost duration 2 hours
There are other values in the chart relating to over, under, disconnects, etc...

What values would you suggest?
 

John61CT

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The ones recommended by your batt mfg.

EQ should mean "equalize", which if used to mean the regular say monthly higher-voltage routine to prevent sulphation, aka "conditioning" should be disabled, only do this manually.

"Boost" likely means Absorb setpoint.

Let's say mfg states Absorb should be 14.2-14.4, and 100% Full is defined as Trailing Amps dropping to .01C, or 1A per 100AH.

Put an ammeter of some sort on the batt, start with all loads off and the bank discharged say 30-40%.

Charge at Absorb, and see what current is being accepted when the SC goes to Float. If higher than spec, increase the Absorb hold time until it's right.

Then do the same with your usual loads running.

The goal is to try to hit that low amps number 90% of the time. Going too low /long sometimes is better than regularly too high /early.

Better of course for the charge sources to actually be controlled by a shunt-based SoC monitor e.g. Bogart Trimetric and their SC-2030.
 

galladanb

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Update:
I just spoke with a Renogy tech and he felt like I do that the controller and charger are likely sensing each other and then doing no charging. That does not mean either is defective, just that they each "see" the correct voltage, then cycle down. He suggested that I add in some sort of isolation switch to force one system or the other to do the charging.

On other words, turn the charger inverter off on sunny days, and turn off the solar system on cloudy days and when plugged into a shoreline.

Sounds good, just not the way I had envisioned. In other words, I wanted my van to be semi automated. Shoreline charging when plugged in, and solar when not.

I will have to figure out some other way to do that better?
 

Wabbit

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I have some Duracell 215ah 6v(x2). Just bought within last month. I am planning on doing my own EQ monthly when the sun will be good for that day. These Duracell's are East Penn Dela clones(ish).

My set points.

EQ 15.3 - 3 hours
Boost 14.8 - 3 hours
Float 14.1

I am new to being nice to batteries. Before I just bought a deep cycle 120ah marine 12v battery and replaced every 18-24 months. These set points are from East Penn for deka batteries that are supposed to be what mine are clones of. Not saying my set points are correct for your batteries, just what I am trying. If I wreck em that just knowledge gained for next time. G'luck!

EDIT: Water level recommended at 1\8 inch below where water meets plastic. Not 1\8 below caps. Hope that makes sense.
ANOTHER EDIT: These batts are more like 157ah @5a draw.
 

galladanb

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Wabbit said:
I have some Duracell 215ah 6v(x2). Just bought within last month. I am planning on doing my own EQ monthly when the sun will be good for that day. These Duracell's are East Penn Dela clones(ish).

My set points.

EQ 15.3 - 3 hours
Boost 14.8 - 3 hours
Float 14.1

I am new to being nice to batteries. Before I just bought a deep cycle 120ah marine 12v battery and replaced every 18-24 months. These set points are from East Penn for deka batteries that are supposed to be what mine are clones of. Not saying my set points are correct for your batteries, just what I am trying. If I wreck em that just knowledge gained for next time. G'luck!

EDIT: Water level recommended at 1\8 inch below where water meets plastic. Not 1\8 below caps. Hope that makes sense.
ANOTHER EDIT: These batts are more like 157ah @5a draw.

Thx, I think that is the ones I have also... I got mine at the local SAMs club, and I believe they were named "E GC2" they have the gray colored cases...

So, when you say your going to do your own EQ monthly, please explain? How do you I niate it manually? Are you doing it from the solar controller, or some other way?

Where did you get the set points from? I'm assuming my batteries would be similar?
And where did you set the set Points? In your solar controller, or???
I think I can adjust my controller numbers as you suggested if that will help?

I filled to just shy of the plastic inner/lower rim, so I think I did good....
 

John61CT

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> he felt like I do that the controller and charger are likely sensing each other and then doing no charging.

This will actually cause no problem,
 

John61CT

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Those Duracells from Sam's are made by East Penn, so follow those setpoints.

For holding Absorb (boost):

​Absorption End Point = Current change over 1 hour period of less than 0.1A
 

Trebor English

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galladanb said:
Update:
I just spoke with a Renogy tech and he felt like I do that the controller and charger are likely sensing each other and then doing no charging. That does not mean either is defective, just that they each "see" the correct voltage, then cycle down. He suggested that I add in some sort of isolation switch to force one system or the other to do the charging.

If you want 14.6 volts and the battery gets to 14.6 volts does it matter whose fault it is that the desired 14.6 volts was reached?  At 13.8 volts you can have all available amps.  Why would you want to turn off one source of amps?  Forcing one system to do the charging by disconnecting the other reduces the max amps and makes it so that if you do forget to switch as necessary you get no charge.

One of the functions of the solar charge controller is to stop when the battery is full.  If your two charging systems both saw the battery as full it seems to me appropriate for the charging to stop.  The two charging systems both see the battery voltage.  They don't sense each other.

After adding a half gallon of water the specific gravity should be off the chart low.  Disconnecting charging sources won't fix that.
 
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