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Equalizing batteries

Looks like the setting on the xantrex may have been wrong for my AGMs. I'm thinking they probably haven't been equalized so my questions are do I need to disconnect the starter batteries? Also I have 15 amps coming in on the circuit I'm using. Is this enough or should I use the generator? Should I do the same for the red top starter batteries which won't turn the motor over without the boost switch. Anything else I should be aware of? Thanks
Build 5477
99 3602 WTFE U270C

Re: Equalizing batteries

Reply #2 –
I have my coach batteries charged by solar and  every 28 days they get a short (4 hrs) boost at 14.8v to make sure they are topped up. Not quite Equalizing but sort of. Mine are Lifeline AGM.
It seems batteries never tend to get a FULL charge so this tries to do that, although not too frequently.
My 3  8ds are now 4 yrs old and seem to be fine and we basically live off them when on road.
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Equalizing batteries

Reply #3 –
AFIK, Lifeline is the only battery manufacturer who recommends equalizing their AGM batteries, and only when the batteries have suffered a more than gradual loss of capacity, and with a very specific regimen. East Penn/Deka says not to EQ their AGM (or GEL) batteries. AGM batteries will suffer a loss of capacity if they aren't fairly consistently recharged to a 100%, or if they are often cycled to below 50% SOC. First thing to do is to be sure of what kind of batteries your coach has, and what brand. The red top starting batteries may be toast. If the coach has sat for long periods of time (even plugged in), the parasitic draws will damage the red tops (or really any other battery) over time, unless you have a supplemental charging system to specifically charge the start batteries. Lots of posts on that topic! If the coach is not parked for long periods and driven reasonably long distances often enough, the alternator should keep them healthy. Periodic use of the boost switch while parked can accomplish the same thing.
Don
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Equalizing batteries

Reply #4 –
Parasitic loads...Reason why I disconnect all batteries while in storage.
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: Equalizing batteries

Reply #5 –
This is what I read that made me think it might be beneficial. On the starter batteries should I try using my auto battery charger to charge separately? I;m guessing it won't hurt. As far as parasitic  loads will turning off the house switch coming in the entrance eliminate draw from the batteries?
Page 18
http://www.xantrex.com/documents/Inverter-Chargers/Freedom-458/Freedom458%28445-0193-01-01_rev-2%29.pdf
Build 5477
99 3602 WTFE U270C

Re: Equalizing batteries

Reply #6 –
I would disconnect the Red Tops from each other and try charging them separately, provided your automotive charger has the right charge parameters. You might find that one of the two is toes up or that they are both weak. Two new red tops cost around $400. I put one O'Reilly AGM8D in their place at a cost of $449. Simplified the cabling a bit and now cranks as it should. I have had a number of Optima batteries in various applications go belly up prematurely and even when getting a free replacement, too much hassle so I won't be getting any more of those. Other people have had better luck with them... The switch at the door doesn't turn off any loads to the chassis batteries and doesn't turn off ALL loads to the house bank for that matter. The breaker panel beneath the white fiberglass cover in the storage bay has two columns of breakers. The one on the left which includes the fridge, propane detector, remote locks (if equipped), etc. are not affected by the switch by the door. The column on the right which is lighting, power seats, etc. is controlled by that switch.
Don
Quote from: goldbehen –
This is what I read that made me think it might be beneficial. On the starter batteries should I try using my auto battery charger to charge separately? I;m guessing it won't hurt. As far as parasitic  loads will turning off the house switch coming in the entrance eliminate draw from the batteries?
Page 18
http://www.xantrex.com/documents/Inverter-Chargers/Freedom-458/Freedom458%28445-0193-01-01_rev-2%29.pdf
The selected media item is not currently available.
Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Equalizing batteries

Reply #7 –
To answer is 15 amp service enough to equalize question-- absolutely.  You should only equalize after the batteries are at full charge.  So, you are talking about very few amps, just higher voltage.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020
 

Re: Equalizing batteries

Reply #8 –
Equalizing by definition charges battery at a higher than normal voltage, which usually causes electrolyte to 'boil' or gas and in a flooded battery, eventually requires adding water to cells.  The higher the charge voltage and the longer it is applied, the more the chance of boiling.

Sealed GEL & AGM are VRLA batteries (valve-regulated lead-acid) and are manufactured with an internal pressure that must be maintained for the battery to function.  Since these batteries can gas if incorrectly charged, to prevent the increased pressure from causing the battery to explode, non-removable emergency pressure release valves are used in place of cell caps.  Caps must not be opened and lost pressure cannot be replaced, possibly causing battery to prematurely fail.

The "correct" charge voltage is much lower for hot batteries and much higher for cold batteries, so having a temperature compensated charger is highly recommended for sealed batteries. 

Normally VLRA sealed batteries are not equalized, and when the charge profile is set to GEL or AGM, equalize setting is disabled.

Following is a quote I found on the Internet:

 "As with all gelled and sealed units, AGM batteries are sensitive to overcharging.  These batteries can be charged to 2.40V/cell (and higher) without problem; however, the float charge should be reduced to between 2.25 and 2.30V/cell (summer temperatures may require lower voltages).  Automotive charging systems for flooded lead acid often have a fixed float voltage setting of 14.40V (2.40V/cell), and a direct replacement with a sealed unit could spell trouble by exposing the battery to undue overcharge on a long drive.

AGM and other sealed batteries do not like heat and should be installed away from the engine compartment.  Manufacturers recommend halting charge if the battery core reaches 120F.  While regular lead acid batteries need a topping charge every six months to prevent the buildup of sulfation, AGM batteries are less prone to this and can sit in storage for longer before a charge becomes necessary."