Charging my batteries

[stans02]

I left the main power switch on, and now I have a couple dead batteries.( 2 6v) I have a 6 amp 12v charger. How long should I leave it charging with 6 amp to bring it up to full charge? Thanks Stan

[RoyBraddy]

Here is a Progressive Dynamics Brochure report on how it takes to charge a battery using different DC VOLTAGES... Maybe you can judge better from this. It will be many many days to get to a full 100% state of charge in your case.

"Progressive Dynamics ran this test on the amount of time it took a PD9155 (55-amp) converter/charger set to three different output voltages to recharge a 125 AH (Amp Hour) battery after it was fully discharged to 10.5-volts.

14.4-VOLTS (Boost Mode) – Returned the battery to 90% of full charge in approximately 3-hours. The battery reached full charge in approximately 11 hours.

13.6-VOLTS (Normal Mode) – Required 40-hours to return the battery to 90% of full charge and 78-hours to reach full charge.

13.2-VOLTS (Storage Mode) – Required 60-hours to return the battery to 90% of full charge and 100-hours to reach full charge."

Keep in mind the current available in the above test is 55AMPS. The established rule of thumb among us RV'ers is to use around 20AMPs of available current per battery being charged.

It is usually better to connect the trailer to shore power and re-charge the batteries using the on-board smart-mode technology converter/charger system. I would also leave the two 6V batteries connected in series and consider them as ONE 12VDC battery. I also would not use more than 14.4VDC as charging voltage.

Depending on how long your two batteries have been fully discharged you may already have done too much damage to them to recover. If a battery drops below 10.5VDC (approximately 0% charge state) then battery failure is imminent. You may have to replace your batteries. Most of us do not like discharging our batteries more than the 50% charge state (approximately 12.0VDC) before re-charging again. I can do around 10-12 of these 50% to 90% charge states cycles when camping off the power grid and then I must do a full 100% charge state before doing damage to my battery bank.

Just my thoughts
Roy Ken

[cb1000rider]

Stan,
If you completely discharged your batteries, you may have damaged them and they may never return to the prior state before discharge.
If I were you, I'd charge on 6A for 1.5 days, then switch to a floating charger. While you're in there, check the water level of those batteries.

[BobK]

I've had several problems with my Greyhawk 31FK where the starting battery was run down after the rv had been sitting in my yard for a few weeks. There are several things in the RV that do not have to be turned on to draw some power. I bought a battery switch at an auto parts store. The battery switch attaches to the battery post and then has a post that the battery cable attaches to. When parked for more than a day or so I open the hood and lift the battery switch lever to completely disconnect the battery. No more problems with a low battery.

[Mustang65]

I would go along with Roy's Progressive... charge controller specs, but I would start the process on a day where you can keep an eye on the recharging. Every few hours checking the battery to see if they are hot, check the charging voltage levels and check the water levels in all the cells (Wear safety glasses). After about 8 hours, disconnect the shore power, let the batteries sit for about an hour and then take a voltage reading across each battery. They should be close, within a couple of tenths of a volt within each other. If not you may have a battery that is not going to survive. If they are both within the limits of the mfr, and are not hot, they should be ok and continue charging them. Just keep checking them, and the water levels, as charging batteries will need to have water added.

Just my thoughts,
Don

[kennyc]

Does shore power on a 2005 Escapade 28G charge the house batteries or do I need to put them on a battery charger?

[RoyBraddy]

KENNY C-When in doubt always grab your multimeter and check across the battery terminals. Without Shore Power connected you will see around 12.6-7 VDC if your battery is fully charged.

When you turn ON shore power then this reading should jump to 13.6VDC or what smart mode charging your converter/charger is in. IT might be as high as 14.4VDC when you first plug in SHORE POWER. Most often it reads the normal DC VOLTAGE coming from the Converter/charger which is 13.6VDC.

Roy Ken