How Often Would You Do An Equalization

[Sacrebleu]

My question is how often should one do the "equalization" on the battries? I have open lead acid battries on board and they are behaving fine and holding their charge.

[zeehag]

why fix what aint broke.....just sayin...

[ReMetau]

You do it when it needs it. Measure the specific gravity and when the cells are different or not holding a charge like it used to, then it is time to equalize.

[Sacrebleu]

Thanks for that Don. I will measure the specific gravity first. I was really just curious how often it is done.

[delmarrey]

I did an accidental equalization (2 amps for three days) on one of my gp 27's and I noticed it kept a higher voltage then the other battery for a long while.

[AnchorageGuy]

Our Iota battery charger will automatically go through an equalization mode every week. Since we installed this charger the batteries have never been very happier. A lot will depend on the discharge/charge cycle and how often and how deep you discharge the bank. I would recommend it as a monthly maintenance. Chuck

[btrayfors]

I'm a big fan of Iota chargers, too. I have had two of them (DLS-55/IQ4 and DLS-45/IQ4) for over five years, in use 24/7. I've also installed a bunch of them on client's boats.

However, the "equalization" cycle claimed by Iota is NOT a true equalization cycle. It's really a "repeat bulk/absorption" cycle, which never gets anywhere near the 15.5 to 16.5VDC needed for true equalization. It's my one big gripe about Iotas, and I wish they'd revise their documentation and stop claiming the weekly "equalization" cycle.

I've studied these chargers pretty carefully and they're absolutely the best bang for the buck. However, plate sulfation still does occur at the voltages permitted by the IQ4 smart charge controller, though very slowly.

The Iotas are particularly good for quick charging during a cruising boat's cycle from, say, 50% to 85% state-of-charge. They're also good for continuous usage at dockside or in solar installations ashore.

Even better life can be had from your batteries, however, if you periodically do a true equalization cycle, using another charging source which elevates the voltage to at least 15.5VDC to 16.5VDC for several hours. Every six months or so might make sense for a typical installation.

I have several chargers capable of delivering true equalization voltages, and I've found that periodic treatment of the batteries normally maintained by the Iota chargers does, in fact, make a significant difference in restoring battery capacity.

Also, not widely known is the fact that the Iota's normal charging voltages can be "pulled" up or down somewhat. For maintaining my T-105 banks, I've bumped the Iota's voltages up to:
15.0 bulk, 14.4 absorption, and 13.8 float.

You would not want to do this unless you are driven to monitor your batteries carefully.

Bill

[goboatingnow]

Originally Posted by btrayfors

I'm a big fan of Iota chargers, too. I have had two of them (DLS-55/IQ4 and DLS-45/IQ4) for over five years, in use 24/7. I........

Also, not widely known is the fact that the Iota's normal charging voltages can be "pulled" up or down somewhat. For maintaining my T-105 banks, I've bumped the Iota's voltages up to:
15.0 bulk, 14.4 absorption, and 13.8 float.

You would not want to do this unless you are driven to monitor your batteries carefully.

Bill

How can " bulk" voltage be set at 15v. In bulk mode a charger is on constant current mode it's voltage is well below the absorption level. 15v is just nonsense.

Dave

[btrayfors]

Originally Posted by goboatingnow

How can " bulk" voltage be set at 15v. In bulk mode a charger is on constant current mode it's voltage is well below the absorption level. 15v is just nonsense.

Dave

Sorry, Dave, it's not nonsense. It's true.

During the bulk phase, the charger puts out its full rated output -- and sometimes more -- and voltage rises until it reaches the bulk voltage set point. After that, voltage is limited -- to less than the bulk charge set point -- and continued at the absorption level until reaching the float stage.

Many "smart" battery chargers work this way.

BTW, in bulk mode the charger is not necessarily in "constant current mode". Rather, it will deliver all the current the battery will accept up to its full rated output until reaching the maximum bulk voltage.

Here's how Iota describes the IQ4 charging stages:

IQ Smart Charger for DLS Series Battery Chargers from IOTA Engineering

There's a tinly pot behind a small hole in the end of the Iota chargers which allows you to "pull" the voltages one way or another. All three are "pulled"....you can't individually adjust them. In my case, I've found it useful with carefully watched and WaterMiser-capped T-105s to pull the voltages up by about 0.2VDC.

Bill

[Stu Jackson]

Ample Power Company Home Page, tech tab, download the Ample Power Primer. Discusses all four stages of charging, including equalization.

[Sacrebleu]

Thanks Bill for the information. I battery charger I have is a 12v 50amp Sterling Pro Charge Ultra. It does state in the manual that this charger will do an equalization. It takes you through 4 steps to set up the charger and says it takes 240mins to complete then it times out and reverts back to it's previous setting. I will phone Sterling Products on Monday to confirm that the charger does a true equalization.

[btrayfors]

Originally Posted by Sacreblue

Thanks Bill for the information. I battery charger I have is a 12v 50amp Sterling Pro Charge Ultra. It does state in the manual that this charger will do an equalization. It takes you through 4 steps to set up the charger and says it takes 240mins to complete then it times out and reverts back to it's previous setting. I will phone Sterling Products on Monday to confirm that the charger does a true equalization.

It does. I have been testing the 40A model of the ProMariner Pronautic 12-40P which is essentially the same charger. I really like it. It's a great charger. Only wish they made models above 60A output, since some clients require much more charging capacity. But, of course, you can link two Sterlings together to get additional chargiing capacity.

Bill

[Adelie]

Battery Basics says once every 10 discharge cycle, monthly at least.

All about battery equalization says once or twice per year.

Trojan Battery Company recommends when there is a disparity in specific gravity between different cells (>.015) of a fully charged battery.

Equalization says every 10-12 cycles.

Battery Maintenance says every 6mo.

Battery Equalization says weekly

battery equalization | Batteries says after any very deep discharge (>50% DOD?) or when the cells start to have significantly different specific gravities (>.020-.030).

http://www.interstatepowercare.com/P...anual_2007.pdf says weekly.

Preventive Maintenance, Charging and Equalization (605) | Rolls Battery says as needed or every 6mo.


Of the 3 manufacturers here (Trojan, Interstate, Rolls) 1 says weekly, 2 say as needed and 1 says twice yearly regardless of apparent need.

My take from all these sites is that equalization should occur whenever there is a disparity in cell specific gravity which should be checked monthly. Equalization should occur a least twice a year to deal with sulfate buildup that is uniform across all cells.

[btrayfors]

Adelie,

Yes, I'd agree with that.

Thanks for pointing out all the disparities in recommendations.

Understand that often the recommended charging regimes for both batteries and for charger settings are developed by marketing people, not by the engineers who designed the batteries or chargers. And, in general they're pretty conservative recommendations, probably in part to protect from lawsuits.

I would NOT equalize batteries weekly or monthly, despite some recommendations to do so. This is because every time you equalize your batteries you do a little damage to the plates. This accumulates over time.

In my experience and testing, once or twice a year is enough to keep your batteries' capacity at acceptable levels.

Bill

[Tom.B]

So I wonder if the safer non-equalization voltages would make Iota's method less destructive. I see it perhaps more as a parachute for batteries. While it may not have lift like wings, it's surely better than just jumping out of a plane.

Or am I wrong?