Battery questions from the mechanically challenged...
We've got six 6-volt batteries, a 2000 watt inverter and 100 watt solar. There's a control panel which will "equalize" the batteries - which we've never attempted.
The directions are vague at best in the manual.
It does say to disconnect all 12-volt appliances- but how do you disconnect stuff like the built in fans, lights and whatever else runs on 12 volt? Pull all the fuses?
Does it really help extend the life of batteries?
And here's another battery question... If one goes bad, can you replace just the one instead of all six?
KampingKris,FiremanSteve,DaughterCara
Jada - American Eskie princess
2003 GMC Sierra 3500
2006 Alpenlite Limited 34RLR
If you attempt to charge a battery at an excessive voltage for its state of charge, the excess current electrolyzes the water in the electrolyte, producing hydrogen and oxygen gases. The bubbling gases stir the electrolyte. A little bit of this occurs in normal charging.
"Equalizing" is normally done on a fully charged battery, and simply goes a bit farther, producing enough gas to give a fairly vigorous stirring. This can be worthwhile if the electrolyte has become stratified, with a stronger acid concentration near the bottom of the battery than at the top. It's no big deal in modern RV deep cycle battery design, but won't hurt if done every couple of months.
It's uncertain what voltage your controller may use for equalizing, but it may be upwards of 15.5 volts, versus the normal maximum of around 14.5 volts. This could be enough to damage some electronics and shorten the life of bulbs and fans. I wouldn't worry about disconnecting things, but turn off everything you don't need, and do pull the fuse for the fridge control card, for the hour or so of the equalizing cycle. (Fridges use 120 volts for the heater, but 12 volts for the controller and interior light.)
Yes, you can replace one battery in an aged bank, but it's not a good idea. The older sets of cells will register full charge voltage before the new one gets there, so you don't get full capacity from it. If the bank has been properly maintained and used, by the time one battery fails, the others should be very near the end of their useful lives too.
I work with forklift batteries and the equalize option is an important one. So, I was all set to answer this question, but Casey....you covered it all. Very nice and accurate info! Thanks dude!
Normal use builds up lead sulfate on the plates. Equalizing knocks it off. Deep cycle batteries have a special place for all that junk to drop to without shorting out the plates.
Here is more than you want to know about batteries and equalizing.
Built in fans, lights and such you simply TURN OFF.
Fridge, Water heater, Furnace and other 12 volt devices (Air Conditioners may have 12 volt control boards) you take a strip of tape, any kind, scotch, adheasive, eletrical, don't matter
You go to your house fuse panel and you start pulling fuses, stick them to the tape in the same order you pull 'em Put 'em back when done in the same order they are stuck to the tape
NOTE: with a solar control.. If the solar controller is connected DIRECTLY to the battery (or if your converter is connected DIRECTLY to the battery) you may be able to just pop the battery disconnect. That won't work on my rig as the converter connects to the house.
Now: How important is it to equalize.
Good question, and much discussion.. Equalization is needed if a battery gets "Confused" This is easiest to detect with flooded wet cells because you can use a hydrometer to measure the specific gravity of each cell.. Ideally they should all be the same (for this it don't matter what, so long as they are all the same) but over time, and epically if you "Deep Discharge" a time or three, you may find that one cell is way lower than the one next to it.
That is when you need to equalize
Also, on some controllers equalize also helps with "Desulfation"
Sulfates build up on the plates and reduct the battery's capacity, A controlled over charge can help to break these sulfates up and restore battery capacity.
How often do you NEED to equalize/desulfate? Well.. Only when indiacted.. In short it might be a month, or it might be a year, or it might be 5 years
Nothin adds excitment like something that is none of your business John is Near Kenwood TS-2000 housed in a 2005 Damon Intruder 377
Or, if you have it, shut off all the 12vdc power at the kill switch by the front door during equalization.
{Not the battery switch near the batteries.}
Most diesel homes have this switch.
Al C '06 Monaco Exec
wa8yxm wrote: Built in fans, lights and such you simply TURN OFF.
Fridge, Water heater, Furnace and other 12 volt devices (Air Conditioners may have 12 volt control boards) you take a strip of tape, any kind, scotch, adheasive, eletrical, don't matter
You go to your house fuse panel and you start pulling fuses, stick them to the tape in the same order you pull 'em Put 'em back when done in the same order they are stuck to the tape
NOTE: with a solar control.. If the solar controller is connected DIRECTLY to the battery (or if your converter is connected DIRECTLY to the battery) you may be able to just pop the battery disconnect. That won't work on my rig as the converter connects to the house.
Now: How important is it to equalize.
Good question, and much discussion.. Equalization is needed if a battery gets "Confused" This is easiest to detect with flooded wet cells because you can use a hydrometer to measure the specific gravity of each cell.. Ideally they should all be the same (for this it don't matter what, so long as they are all the same) but over time, and epically if you "Deep Discharge" a time or three, you may find that one cell is way lower than the one next to it.
That is when you need to equalize
Also, on some controllers equalize also helps with "Desulfation"
Sulfates build up on the plates and reduct the battery's capacity, A controlled over charge can help to break these sulfates up and restore battery capacity.
How often do you NEED to equalize/desulfate? Well.. Only when indiacted.. In short it might be a month, or it might be a year, or it might be 5 years
* This post was
edited 05/13/08 11:23am by alcolby *
In my post in that thread are two links to sources with criteria for when to do equalization.
If your inverter is an inverter/charger and has the equalization feature, then I suggest you look closely at the connections to the batteries. With a 2000 watt inverter, there should be a heavy wire from the inverter directly to the battery positive (via a large fuse). If you leave only the inverter cable connected to the positive terminal, all the other loads will be disconnected. (A good time to check all the battery connections for being clean and properly tightened.)
The high equalization voltage exceeds the maximum voltage input of many devices in an RV. Some RV's have some circuits that are connected directly to the batteries - such as smoke and lp detectors - and the leaving only the inverter connection prevents them from getting the high voltage.
Mel & Mary Ann; Mo'Be (More Behave...) and Bella
"If you have an RV, you don't need another hobby." Comment from a friend...
73 Kountry Aire 31.5 ft (semi-retired) TT
90 Champion LaSalle MH 29 ft P30 (89 Chassis)
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